This post may contain affiliate links. Please read my disclosure policy for details. As an Amazon Associate I earn from qualifying purchases.
Onsen Tamago literally means ‘hot spring eggs’ in Japanese. It refers to eggs that were originally prepared in hot spring water to create silky egg whites and custard-like yolk. Here’s how you can make this delicious egg recipe at home.
In the past, I’ve shared some popular Japanese egg recipes on Just One Cookbook such as Omurice, Tamagoyaki, and Ramen Egg (Ajitsuke Tamago). Today I’ll add another popular dish to the egg recipe collection, and it’s Onsen Tamago (温泉卵).
Watch How To Make Onsen Tamago
Originally prepared in hot spring water in Japan, this delicious egg recipe with soft silk egg whites and custard-like yolk is easy to make at home.
What’s Onsen Tamago?
Onsen means hot springs, and tamago means eggs in Japanese. Why is the name “hot springs eggs”? Originally, eggs that were prepared this way were slow-cooked in Japan’s warm hot springs water.
What’s so special about these eggs? These eggs are perfectly poached inside its shell. While the whites are soft and silky, the yolk comes out firm but retains the color and creamy texture of an uncooked yolk. It’s basically the complete opposite of soft boiled eggs that are firm whites and soft egg yolk.
The Chemistry Behind Onsen Tamago
This special texture is achieved because egg yolk and egg white solidify at different temperatures. Egg yolks solidify at 158 degrees °F (70 °C) and egg whites solidify at 176 degrees °F (80 °C). Therefore, if we maintain the cooking water to be at 149-154 degrees °F (65-68 °C), we’ll get a perfect spherical poached egg, creamy and silky on the outside and firm on the inside.
This Recipe Works for EVERYONE.
There are many ways to make the perfect onsen tamago, but this technique does not require a microwave, a thermometer, or any special cooking gadget.
Here are the highlights of this technique:
- Requires just a stove and pot (which I hope everyone has in their kitchen).
- Does NOT require a thermometer.
- Use refrigerated eggs. Some recipes require eggs to be “room temperature”, but the “room” temperature could be different depends on where you live.
- Not required to soak eggs in iced water after cooking, in case you don’t have ice cubes handy.
If you follow my recipe precisely, you should be able to achieve perfect onsen tamago as the final result. The only requirement is to use 4 large eggs. If you use different size eggs or reduce/increase the number of eggs, it will not work as the water temperature will change.
How Do you Enjoy Onsen Tamago?
You can enjoy onsen tamago with a dashi-based soy sauce (だし醤油) which is usually served as a part of Japanese breakfast. Also, you can place it on top of the steamed rice, splash some soy sauce over, mix and enjoy; serve with gyudon, curry rice, soba noodle soup, and cold udon; or even mix with carbonara (my favorite!).
Now let’s get started! The best part about this recipe is you do not need to visit hot springs in Japan to enjoy these special eggs. Make the perfect onsen tamago right at home!
Disclaimer: Many people in the world including the Japanese consume uncooked eggs in their cuisine. However, according to the FDA, eggs should be cooked to 165 degrees °F (74 °C) in order to be considered safe. The perfect temperature for cooking onsen tamago is 149-154 degrees °F (65-68 °C), which is below the guideline. There is a risk of salmonella with consuming undercooked eggs.
Japanese Ingredient Substitution: If you want to look for substitutes for Japanese condiments and ingredients, click here.
Sign up for the free Just One Cookbook newsletter delivered to your inbox! And stay in touch with me on Facebook, Pinterest, YouTube, and Instagram for all the latest updates.
Onsen Tamago literally means ‘hot spring eggs’ in Japanese. It refers to eggs that were originally prepared in hot spring water to create silky egg whites and custard-like yolk. Here's how you can make this delicious egg recipe at home.
- 1000 ml water (about 4 cups)
- 200 ml tap water (little bit less than 1 cup) (needs to be colder than room temp)
- 4 large eggs (50 g each w/o shell) (refrigerated)
- ¼ cup dashi (Japanese soup stock; click to learn more) (for vegetarian use kombu dashi)
- ½ Tbsp mirin
- 1 ½ Tbsp soy sauce
- 3 g katsuobushi (dried bonito flakes) (skip for vegetarian)
- 1 green onion/scallion (for garnish)
-
Gather all the ingredients. You will need a small heavy-bottomed saucepan (I use 1.5 QT); the water should cover the eggs with 1000 ml water completely.
-
Add 1000 ml water in the saucepan, cover with a tight-fitting lid, and bring it to a boil.
- Once boiling, remove the pot from the heat. Take the eggs out from the refrigerator. Add 200 ml cold tap water and gently submerge the cold eggs in the hot water. Immediately cover and set the timer for 17 minutes.
- If you like to enjoy onsen tamgo with the sauce, combine the dashi, mirin, and soy sauce in a small saucepan and bring it to a boil. Add katsuobushi and turn off the heat, let katsuobushi sink at the bottom of the pan. After 30 seconds or so, strain through the strainer and set the sauce aside. You can keep the sauce in refrigerator for 4-5 days.
- Cut scallion into thinly slices and set aside.
- Once 17 minutes have passed, take the eggs out gently and set aside for 5 minutes.
- You can enjoy onsen tamago either cold or warm. Crack the egg and pour the sauce over, garnish with chopped scallion.
-
You can keep the uncracked onsen tamago for 1-2 days in the refrigerator. To reheat, take out the onsen tamago from the fridge to room temperature. Place it in 160 ºF(70 ºC) water for 10 minutes to warm up. Do not reheat higher than that otherwise the egg will be cooked.
Equipment you will need:
- 5 qt saucepan with lid (make sure water will cover eggs)
- A ladle or mesh strainer
Recipe by Namiko Chen of Just One Cookbook. All images and content on this site are copyright protected. Please do not use my images without my permission. If you’d like to share this recipe on your site, please re-write the recipe in your own words and link to this post as the original source. Thank you.
I LOVE onsen tamago. I followed several different ways to make this – this is the by far the easiest! (I love it with rice and a sprinkling of pepper from Nagano.)
Hi Lydia! I’ve done the same, but this method has been the best one that works for me and I hope it’ll be the same for my readers. 🙂 That’s a very nice simple way to enjoy onsen tamago! 🙂
I followed the directions pretty closely with 1000ml of boiling water and 200 ml of tap water: 4 refrigerated eggs at 17 minutes and then testing for 5 minutes. All 4 eggs were still clear with just the edges a bit cloudy… And the took was raw. What do I need to do differently?
*yolk was raw
Hi Lenore! Thank you for trying this recipe. I would adjust reducing 200 ml water and cooking time. Don’t change your pot while you test. You should not change other things and always use the same equipment. I’m sorry yours didn’t work. I wasted a lot of eggs, hoping that I did all the testing for everyone, but I can’t control the condition for everyone. One day I’ll share a recipe using a thermometer. 🙂
This is substantially late to the party but I haven’t seen it mentioned. Keep in mind altitude will affect this recipe greatly. In San Francisco that boiling water will be starting at 212F in Denver it’s only going to be 203F.
Hi Nocturnal! Thank you so much for sharing this information! I’m always curious about how people in high altitude adapt recipes.
That got me thinking…I wonder if food bloggers in higher altitude write recipes in high altitude cooking. Sometimes I don’t check where the food blogger is located and check the recipe directly.
Hi and thanks so much for a great site.. Well done!
I love the sound of this recipe but I would MUCH rather cook them the traditional way.. Ah Japan….
Hope your utube session come together ok and you still have time for a bit of weekend : )
Hi Sally! You mean cooking in the hot spring water? Yeah that’s the best, especially after soaking in onsen before breakfast and breakfast is served… Haha! I miss it….. 🙂
Thank you very much for your encouragement! I’m going to continue tomorrow, too!
Such a nostalgic dish! I can’t wait to make it but I know that I’ll have to make it often for my husband! Thank you for sharing!
Hi Donna! Hope you like this technique and your husband will enjoy this onsen tamago. 🙂 Have a wonderful weekend, Donna!
Wow, thank you! I always wondered how these eggs were prepared at the Japanese hotels (had them at some breakfast buffets).
Hi Wendy! It’s actually very simple (simpler) than making a regular poached egg I think. 🙂 Hope you try this recipe at home!
Goodness yes, this is FAR simpler than poaching eggs, speaking from professional experience. One of the biggest nightmares every chef has is poaching eggs to order. That same nightmare usually includes Mother’s Day. Onsen eggs are a cakewalk by comparison. 🙂
Hi Robert! Aw I’m happy to hear from a chef! Thank you so much for your comment and confirming onsen tamago is easier. 😀 Haha, it’s funny you mentioned about Mother’s Day. I wonder how many orders of poached eggs you have (had) to make on that day…. 🙂
This looks delicious, but is the egg cooked through? If I served this to my mother she’d freak lol, so I was just wondering c:
Hi Kathryn! Well it’s not cooked “fully” so it’s probably not for your mother. 🙂
If the water in the pot is 176 degrees °F (80 °C), you can safely put in a single egg and up to four given your 1 Litre (quart+-) of boiling water + 250ml (1 cup) tap water. The thermal mass of the water is what is needed to properly cook the eggs. Adding a 5th egg will probably lower the water temperature too much & affect the outcome.
I think that using the amount of water specified, 1-3 eggs of any size can be safely cooked, maybe not for the 4th because the weight of the eggs would cause the water/egg weight ratio to be changed.
However, if you increased the amount of boiling water and tap water in their 4 to 1 ratio, you can cook a larger number of eggs properly.
If you have a sous-vide machine – just set the temperature to 149-154 degrees °F (65-68 °C) & wait 17+ minutes.
You may need to do a test run, but it isn’t rocket science.
PS. I just gave up poaching eggs (in water). This is much easier, less mess.
Thank you Al! I got a sous-vide machine so I look forward to testing with it too. 🙂
Appreciate this comment; I am immune suppressed and so cannot really tolerate the risk for undercooked eggs. Four at a time sounds right, so likely I’ll just increase the water amount a little for safety when I get around to this one.
Hi Nami,
I tried your Onsen Tamago recipe of today with one egg. It turned out perfect and exactly how I like my soft-boiled eggs. Thank you!!
Hi Marguerite! I’m so glad to hear it worked! Thank you very much for your kind feedback! 🙂
I’ve lived in Japan 42 years and recipes like this are a wonderful way to help others enjoy our great food. Keep motivated, keep cookin’
Thank you so much, Joe!
You always make it look so easy. I definitely want to give this a try if I can get my hands on some really fresh eggs. I am sure I can eat all 4 in one sitting but I probably shouldn’t….
Thank you Kit! Hope you enjoy this recipe! 🙂
Thank you so much for posting this! I made this with two eggs and added them to soup and it was one of the best and most comforting breakfasts I’ve made myself in awhile!
I’m so happy to hear you enjoyed this recipe! Thanks you very much for your kind feedback! 🙂
Hi, Eggs are my favorite. I will try the 17 minute method of cooking and use the sauce receipe you provided.
Thank You.
Hi Alexandria! Hope you enjoy this recipe! 🙂
I finally made it! 🙂 I failed the first two times, and I got almost hard boiled eggs… Later I discovered that I actually missed out adding 200ml tap water in step 2… haha~ So I tried again yesterday night, and I.made.it!! 🙂 So so happy~ The next time I do it again I’ll take a picture of it and show it to you on your FB 🙂
Hi Jessica! Haha! Yeah the water is to lower the temperature (without using a thermometer). 😀 I’m glad yours came out well. Thanks so much for trying this recipe. Yep, I look forward to your photos! 😉
I finally made onsen tamago using your recipe. It is spot on and I loved how the egg slipped out whole when you crack the egg in two. I am pointing my friends to this direction as they are asking me how I did it. Thanks Nami!
HI Maricel! I’m so glad to hear your onsen tamago came out well! Thank you so much for writing your kind feedback and referring your friends to my site. You’re too kind! Thanks for your support! 🙂
My eggs cracked as soon as they hit they water. Is it possible that my cold water wasn’t cold enough to cool it and the temperature change from the fridge to the water was too drastic?
Hi Samantha! I always make it this way and I have no issues. It’s obvious but just in case… you didn’t drop it right? Make sure to lower the egg one by one using a ladle or slotted spoon to place on the bottom of the pot, not “dropping off”.
Finally the mystery behind the onsen tamago is revealed to me after over a decade when i encountered them at a hot springs in Japan. I thought it was just the novelty of hot spring boiled eggs. I never tried as i am intolerant to eggs although i love them (looking at recipes to cook for someone else). I think my nephew will love these as he loves poached eggs.
Hi Kenny! Aww I’m so glad this post give you a closure. 😀 I hope your nephew will enjoy Onsen Tamago. 🙂
Mine did not come out whole. The whites were stuck to the shells. The yolks were perfect though. Any ideas on what might have gone wrong? Thank you!
Hi Andrea! Sorry it didn’t come out well. Although I’m not 100% sure what went wrong as I wasn’t there with you in the kitchen, but I heard one reason why egg whites get stuck with the shells. If you have just bought these eggs and made this recipe, it’s possible that your eggs were too fresh. It’s funny, but to make this egg or boiled eggs, it’s easier to use a little bit older eggs (I remember reading somewhere that we should use the eggs in the fridge for at least a week) as shells come off nice and easy (You can probably google about it). However, I have made this recipe with fresher eggs (ones I bought from a store), and didn’t have this issue… So to be honest with you, I’m not too sure… Sorry I wish I could help.
This exact problem happened to me! Otherwise the eggs turned out great tastewise but just didn’t look as good. The yolk was separated from the white which were in pieces some stuck to the shell.
Hi Jen! So the egg white was cooked and attach to the shell? Is it possible it’s overcooked so it is more like hard boiled egg? Did you use refrigerated eggs? It’s important that they were not at room temperature as the starting point would be at different temperature.
Woah. these eggs came out just great! I searched for the ramen recipe on your site but there’s none. Since I don’t want to screw up another time with it, I thought your version would be the most balanced. Yeah.. so that’s a hure request from me! Show us some nice ramen c:
Hi Keith! I’m happy to hear you liked the recipe! I have two ramen recipes and chashu recipes on my site. Search ramen and it should come up. 🙂
Hi Nami! thank you for this incredibly easy to follow way to create onsen-tamago. I used to make them in thermos jars with a thermometer constantly on standby, this is much much easier. I love your other recipes too, thank you for all you do 🙂
Hi Carol! I’m happy to hear you like this recipe! I get a lot of feedback from readers and I wanted to make a recipe that everyone can make using only things most people have… 😀 Thank you so much for reading my blog!
Followed step by step but started to removed eggs from covered pot at 1min intervals (at 15mins) and found the best two to be 16-17min mark.
Thanks for sharing this Nami.
That’s exactly what I did too! I’m glad you found the cooking time for your perfect onsen tamago! Thank you for trying my recipe! 🙂
This is a great recipe! I had to leave the eggs in the water for 22mins but it was awesome. Love the texture of the egg! Thanks for sharing!
Hi Jannica! I’m glad to hear you figure out the time that works for you! From now on, you know how to make perfect onsen tamago every time if you use the same pot, etc. 🙂 Thank you so much for trying my recipe!
Hi Namiko,
I love your recipes, it has been a life saver since I moved to Japan!
I tried to make onsen tamago but the egg cane out totally raw. It’s 2 degrees now, and the tap water is icy cold and that could have been the reason. Could you advise what I can do with water of such temperatures for adding to the boiling water?
Thank you!
Chloe
Hi Chloe! I hope you’re enjoying your life in Japan! 🙂 Ah I just remembered how cold tap water was in winter (I’m used to California tap water temp now). I totally agree – that could be the reason. Your cold water was more like iced water…. 🙂 Reduce the amount next time – you have to experiment a little bit. Cut down to half to see how it works next time?
Hello
I’m planning to make onsen tamago this Sunday, but I need 5 eggs (as there are 5 people). In your recipie you state that this only works with 4 eggs. Do you have an idea how I could make it work for 5 eggs.
Ronja
Hi Ronja! The weakness of this recipe is that we can’t change the number of eggs. When you add 5 eggs, the temperature of the hot water will decrease more. I haven’t tested recipe with 5 eggs, so I don’t know how long the eggs will take to cook perfectly. Sorry… I usually keep the egg for next day when I make extra. 🙂
Hi, Nami!
I’ ve tried the egss this morning but they turned out hard boiled eggs :(. Mayb i used small to medium eggs instead of large one, so mayb i should reduce the time from 17 mins to 15 mins or shorter? If i only cook two eggs, should i reduce time as well? Thx for your time! 🙂
Hi Nina! Thank you for trying this recipe! As I mentioned, this recipe only works with 4 eggs. 2 additional cold eggs that you didn’t add supposed to lower the temperature of the boiling water. The size also matters but you can easily reduce the cooking time. We use different pot, so you might need to adjust the cooking time and require some “practice run” before you get the perfect onsen tamago. 🙂
I did my first attempt with just 2 eggs in a smaller pan (holds about 800ml) so the eggs would stil be covered completely by the water. I used 600ml of water to heat up and 120ml of tap water to cool down. Took out the first egg at 17min, the yolk was still partially runny. Took out the second egg at 18min and the yolk on that one had a very even consitency. The whites were still quite fluid though (is this as it’s supposed to be?) – will try 19min on the next run and see how that turns out. But all in all turned out very nicely for my first attempt, thanks for the recipe 🙂
Hi Raphael! Thank you so much for sharing! A lot of readers want to make 2 eggs, so your input will help many JOC readers! Thanks again!
I tried making this today and followed the recipe exactly but the eggs were so runny still the whites had near no firmness and were mostly goo, the photos looked like it was solid enough to hold its shape . I’ll probably try it again without the cold water. All your recipes look so yummy. I bookmarked many to save. Thaks for sharin .
Hi Crystal! Only difference between my eggs and your eggs are….
– different pot and lid
– different egg size (even though it can be both “large”).
tap water temp and refrigerator temp should be pretty much same. Different pots/lid transfer heat differently, and maybe yours escape heat faster hence colder water to cook eggs.
If you’re going to use the same pot, cook longer, or reduce the amount of water etc to bring up the temp or simply cook longer. I did a few experiment to make sure the outcome is good, but we all have different pots, so that can be tricky…
I’m happy to hear you find some recipes you want to try from my blog. Hope you enjoy them! 🙂
If I am doubling the recipe, do I wait longer than 17 minutes?
Hi Mary! Unfortunately it doesn’t work like that. I made this recipe, specifically for people who don’t have thermometer. It’s very precise when it comes to the water temperature and cooking time. So if you add more eggs, the water temp will drop drastically, and even you cook for a longer time, the result will not be the same. So for this recipe, it only works if you follow the recipe (and use a similar thickness of pot – so heat won’t escape much). 🙂
Hi Nami:
I attempted making onsen tamago using your recipe and wow so so lovely. Thank you!
By the way, while searching for something online I came upon this gadget, a yellow half-boiled egg cooker from Malaysia (http://bit.ly/2cdnwZT). It is written that local coffee shops still use them. I’d love to hear what you or other readers know about it. I do question the use of plastic though. Also not sure about another one-purpose gadget for the kitchen.
Hi Christina! I’m so happy yours came out well! I’ve never used or heard of this gadget until you mentioned. I know Instant Pot (pressure cooker) makes great eggs too, which has multi functions… so I’d highly recommend that instead of this one. 😀 Though, Instant Pot is American size and too big for some kitchen (like Japanese kitchen…).
Hi Nami! I tried making these eggs as a core component of ontama udon, but it seems like I failed to get it cooked enough 🙁
From what I understand it’s also common to eat the egg raw and I didn’t mind it and went ahead and ate it, but it was less cooked than pictured and intended. Some of the whites were still transparent and more runny. Any advice on what I might be doing wrong/how I can improve it?
Thanks!
Hi Lyanne! I created this recipe so that it’s not required my readers to use a kitchen thermometer (not everyone has it), you have to follow the recipe exactly. The number of eggs, water amount, everything matters to create the perfect water temperature to cook the eggs.
Having said that, the only difference between mine and yours is our pots. Mine could be more insulated if yours didn’t cooked enough. Maybe your pot might escape the heat more, or your kitchen can be colder than my kitchen. That could be the only difference, as refrigerated eggs and running water from faucet should be pretty similar temperature. If you follow the recipe exactly and ended up with less cooked eggs, you could:
1) cook for a longer time
2) add less water
which will help cook the eggs. But then you’ll have to measure the cooking time etc and experiment… I spent some time making this recipe testing time and temperature (lots of eggs used for testing recipes!)… I really hoped that people didn’t have to go through all that troubles…
Sorry yours are undercooked. Hope you can figure out the perfect temp or time to cook your eggs. 🙂
My Onsen tamago turned out perfect! Thank you!
Hi Angela! I’m so happy to hear that! Thank you for letting me know! 🙂
SImple and easy, thanks.
Thank you for checking my recipe! 🙂
I screwed up the first time I missed out on step 2.
Hi Bill! Oh! You forgot to add water? 😀
When you crack the egg, how do you make sure it comes out ‘intact’? You cant peel it for obvious reasons since the white is still runny. Thanks.
Hi Al! If you crack the eggs like how you normally crack, you won’t damage the onsen tamago and it won’t break easily unless you poke it etc. 🙂
IF using refrigerated eggs, wouldnt the eggs crack upon contact with hot water?
Hi Zac! No, it won’t. I always use this method and I don’t have any issue. But make sure you don’t “drop” the eggs into the water. You have to gently submerge them…. 🙂
Thanks for the reply Nami. I tried it, it didn’t crack! Which is strange because when I did soft boil eggs, it cracked due to thermal shock. Anyway I tried this recipe but eggs were undercooked, still transparent. I’ll adjust accordingly. I also tried the ramen egg recipe and it worked! Except for 1 smaller egg which is more cooked due to its size haha.
Hi Zac! This recipe (without using thermometer) works perfectly when we have exactly same products and condition…. which is kind of hard to achieve. We got to use same pot (each one conduct heat differently) etc. So please test the cooking time. I had to test several eggs to figure out cooking time for me. But once you know, just use same pot and it should work every time. 🙂
Absolutely delicious! 😀 Ended up eating three in a row when they were done.
(Baaad idea; eggs is still eggs!) I recommend eating only one at a time, no matter how tempting they may look.
Hi Liz! Haha 3 in a row! 😀 But I can’t laugh as I probably ate more when I was testing this recipe for the perfect cooking time… What else could I do… I didn’t want to throw away food…. xD
Hi, Nami. I just tried making onsen tamago following your recipe this morning. Unfortunately, even though I followed the recipe exactly, the eggs did not turn out right. The whites were very runny and the yolks overcooked to a point that they became custardy. What do you think could have caused this to happen? Thank you.
Hi Veronica! Hmm hard to tell what went wrong or what could cause your result. As this method doesn’t use a thermometer, tools, eggs, and water temperature makes a difference. A type of pot (how heat transmit to egg) and the number of eggs are very important factor. I had to test with several eggs to find out the timing with my pot and eggs, but it may be different from yours. I recommend using the same method (pots, egg, water) to find your time, and then keep using the same approach. Hope this makes sense.
I just wanted to put some info down and see if anyone has information for my issue with this recipe (it’s actually a problem with almost any egg recipe where they are cooked inside the shell):
I live in a pretty high altitude and I think this is affecting the eggs. Even at more than 25 min in, the white were raw and runny (at 25 min was when the water started to noticeably cool so I didn’t try past this). The last egg had started to turn white, but clearly was far too undercooked.
I would love to make this recipe, but I’m not sure if I should even add cold tap water at all in this case. I have a pretty good idea of how long to cook both hard and soft boiled eggs, but it took years of asking others who live near me and playing around with temps to get it to work. Any suggestions would be helpful as I’m almost a dozen eggs into trying this (at 4 eggs each time) and I’m not even close.
Hi Kat! I quickly researched in Japanese and I found some article… have you tried cooking for 5 minutes at 85C (boiling)? This person said he made a perfect Onsen Tamago
at 4000 m (http://www.geocities.jp/esashi_ume/Setuzoku/Peru8.htm).
This is Japanese but it’s interesting to figure out how long it takes to make a boiled egg.
https://www.data-artist.com/atelier/20150718.html
Use google chrome to translate to English?
Thanks Nami! I really like that Japanese site (it’s certainly fun to watch the egg cook and I have some knowledge of Japanese so although I couldn’t understand everything, I was able to read some of it). I have found to cook soft boiled eggs here it takes around 7 min (it’s a little less than that) from fridge temp eggs in boiling water.
For this recipe though, would you suggest not adding any cold water to the boiling? I think that might be why they are so undercooked (our water isn’t icy cold). I was trying to get these to soft boiled consistency, but as I noted, even at 25 min, only the barest sliver of white had started turned from clear. I also noticed this: the boiling water reduces temperature rather quickly. I’m on the foothills in Colorado (so we’re pretty high up), which means our water will boil at a much lower temp than other places. Any suggestions for how to cook these eggs? I have a few types of thermometers for cooking (a candy one, a digital meat one, etc), so if you could give me a general temp your water is at after you’ve add the cold water, I can start with that. Thanks again!
Hi Kat! Forgot to answer your question about that water. Yeah I agree. I think you might want to try without adding water. Then if the temperature is too high, you might need to adjust with the water… You must be eating lots of eggs these days. 🙁 Hope you’ll find out the best solution for your Onsen tamago soon! xo
Thank! Okay so here’s my results starting from boiling (my water only hits about 82 degrees C at full rolling boil) and after 25 min, the water had still cooled too far for the eggs to cook (the ending temp of the water after 25 min was only 59C). So I’m getting the feeling that I’m going to have to try to keep the water at a fairly consistent temp. I’m guessing just trying to soft boil them is all I’ll be able to pull off by the looks of how cool the water is here. Is that what your assessment would be too?
Hi Kat! If only 59C, egg yolk won’t become solidified (need to be 70 °C) and egg whites will be impossible to solidified (need 80 °C). Your eggs will be not cooked… 🙁 Sorry… I can’t imagine how hard it must be to cook at high altitude.
These are great directions! I loved this for breakfast, like a little shot of protein. I love eggs, and enjoy your other egg recipes but this is the tastiest!
Aww thanks so much for your kind feedback and compliment. 🙂 I’m glad you enjoyed the recipes. xo
hi nami… perfect recipe ..
although i like the tight eggs … i will try it …
… one question .. how to boil the egg at a lower temperature and be safe….?
(sorry for my english… is not very good)..
Best wishes….
Hi Chris! Maybe this article may help.
Hope this guideline will help: https://eggsafety.org/cooking-eggs-right-temperature/
Hi! I just tried this with four eggs and it’s perfect!!! I don’t know how you come up with such an amazing fail proof recipe.
If I want more than four eggs, do I adjust the amount of water accordingly? Does it work that way?
Hi Joanne! You and I probably use similar equipment and that’s why our outcome was similar. 🙂 I’m sore some people over/undercook because their pot doesn’t sustain the same amount of heat etc… 🙂
No, unfortunately…. you can spend many eggs to figure out if you always make more than 4 eggs. I developed this recipe as 4 seems good number for majority of readers… 🙂
Thanks!
Thank you Henry! 🙂
Hi Nami, Thank you for your wonderful recipe. Tried numerous recipes and your recipe works the best. My kids loved it. The last time I tried it I had the refrigerated eggs taken out of the fridge (700g) when I put the pot of water to boil – That seems to get a better result. I am also wondering how do I adjust the timing so I get the whole egg white out without the liquidy egg white at the sides. Is it important to leave it to rest for the 5minutes when you take it out from the pot? I know you are busy. Hopefully you will have the chance to do the two eggs recipe or using thermal container Thanks!!
Hi Mandy! How about cooking slightly longer to avoid the liquidy egg white? I think it might help. 5 minute is to cook the egg with residual heat. You can experiment with different timing but don’t soak in cold water etc. It will not be enough cooking time, unless you increase the cooking time. Yeah one day I’ll try 2 eggs. Thermal container, maybe. Each brand of thermal container works differently too, so it’s hard to control the heat, I think. 🙂
Hi Nami! I was super excited to try this recipe, but as a few others have reported, mine came out extreamly underdone – I had almost completely clear egg whites! I’m going to experiment with three eggs instead of four and might try adding less cold water before setting them aside to “cook”. I look forward to reporting back with better results 🙂
Hi Brittany! Sorry to hear that yours came out undone. Considering both of our eggs are in the fridge (similar temp), only difference between mine and yours is the room temperature, the heat on stovetop, tap water temperature, and the saucepan (how well you can retain the heat. My saucepan is a stainless steel one and it retains heat pretty well. Was yours thin?). You may need to adjust the amount of water you add… Hope it’ll work next time. 🙂
Why do your directions say to “set timer for 17 minutes (or longer)?”
When / Why would we need a longer time?
Hi Casey! In my cooking condition, 17 minute of cooking is perfect for my liking. Some people may think it’s too runny hence I wrote “17 minutes (or longer)”. It should not be less than 17 minutes. Maybe it’s confusing to write “(or longer)” so I’ll delete this part.
Hi Nami, how are you? I was really looking forward to have Onsen Tamago for our Sunday breakfast, but I made the mistake of not watching the video before, so after submerging the eggs in the water pot, I put it back on the stove and let it simmer for 17 minutes …!!! The result, of course, is hard boiled eggs as solid as rocks, which really made me laugh, but I will use for some other dish …
I will try again soon, hopefully next time I will succeed!!!
Hi Rolanda! Oh no!!! 😀 Hard boiled eggs take 10 minutes or so, so 17 minutes is… overcooked. 😀 Hopefully next one will be a successful one! Thank you for making me smile. Trust me I have a lot of mistakes along the way… 😉
Tried again tonight and I am getting there, even if I think that I need to adjust the timing because of the altitude, which affects the temperature of boiling water. Anyway the sauce is delicious and the egg is fantastic on white rice.
Thanks so much for trying this again! I can’t imagine dealing with the altitude when cooking/baking. Cooking/baking itself is already hard sometimes and to take the altitude into consideration… I would go nuts. Kudos to you!
A dozen eggs later…
For those like me who can’t seem to get it on the first try, I recommend taking one egg out every 5 minutes to figure out how long you’ll need to cook it for. Keep trying till you get the egg of your dreams. Turns out 55 minutes is the perfect time for me.
Hi Tom! I’m so sorry you had to go through what I went through. I guess the difference in our pot, stove, other factors made it difficult. I’m glad you finally figured out the perfect timing for you. 🙂
I’m ServSafe certified and I’d like to point out an error: Eggs don’t have to be cooked to 165. You’re thinking of chicken. The safe internal temperature for eggs that will be served immediately is 145 F. For eggs that will be hot-held for service, the temperature is 155. So onsen tamago should be perfectly safe if you’re going to eat it soon after cooking.
Hi Cookie Weenie! These temperatures are not for food safety, but it’s rather when the egg solidified just to have the texture of Onsen Tamago. I got the temperature info from the Onsen Tamago recipe… But thanks so much for your info!! xo
For the storing instructions, do you keep in the fridge while they are still in the shell? Or you take them out first? Sorry I’m a beginner cook and would love to make this for my husband but I’m confused. Thanks!
Hi Kath! Yes, keep in the shell (maybe you need to draw a mark or put it separately from your regular eggs). When you’re ready to eat, crack the egg and serve. 🙂
I tried this for the first time yesterday, following the recipe precisely and it came out PERFECT! I served it with tonkatsu and rice and it was absolutely delicious. I will make this again and again! Thank you
Hi Elizabeth! I’m so happy to hear you enjoyed this recipe and thank you so much for your kind feedback. 🙂
Thank you for sharing this recipe. I tried it last night and am pretty happy with the first round.
Two things:
1. Yolk not as runny as I like – so I’ll prob try 15min instead of 17min. This is just personal preference.
2. Some of the egg white stuck to the shell in a thin layer vs plopping our with the rest of the egg. I simply used a spoon to scoop it right out.
I’ve been thinking about onsen tamago since tasting them in Japan this year! Thanks to you I can have them anytime now.
Hi Annabel! Thank you for trying this recipe! I’m happy that you’re recreating this dish at home! I’m very curious about (2) situation you had. Do you think rotating the eggs a few times may help cook evenly?
I’ll try rotating my next batch.
Also when I made a 15min (vs 17min) batch the eggs did still “plop” out with no whites stuck on the shells…but was just too runny and didn’t firm up much. I ate them anyway over a salad and had no problems. Eggs are always good.
Hi Annabel! It looks like the egg was just becoming solid and attach to the shell. Another experiment you can do (if this doesn’t work) is to change a pot. Each pot retains heat differently, and this time works for this pan that I use, but if I change, it’ll be slightly different. So if this pot you’re using doesn’t give the best result, try changing equipment around. 🙂
Thanks for all the tips! Love your site and can’t wait to try more of your recipes.
Thank you Annabel! Hope you enjoy cooking more Japanese food at home! 🙂
Hi, thank you for the recipe!
I know you use 4 eggs in your recipe.
Since I cook different number of eggs each time, can you come up with a table to show the number of minutes needed for each case?
Thank you so much!
Hi Mr Ng! I’m sorry I did not prepare that. 🙁
Hi my egges were submerged 3/4. Is that ok? Or should all the eggs be fully submerged?
Hi Georgia! It should be. Maybe your pot size was bigger than mine (and we use same amount of water). I added a note about the pot size in the instructions.
I think the safest way to do this is with sous vide. pasteurization is a function of two things: temperature and time. So, at 65C, 1.5 hrs is perfectly safe.
Since you’re keeping the temperature exactly at 65C with the circulator, the egg won’t over cook and any bugs will be killed with the time at temp!
here is a very useful time/temp chart for pasteurization.
https://i.stack.imgur.com/nFAMT.png
happy cooking!
Doug
Hi Doug! I agree! This Onsen Tamago without a kitchen thermometer is just a hack for those who don’t have fancy equipment or don’t always cook at home. 🙂
Thanks for sharing the super helpful chart with us!!
I’ve made this several times now and it comes out perfect each time! Thank you
Hi Emm! I’m so glad to hear that you enjoy this recipe! Thank you so much for your kind feedback!
What a nice report about the best egg of the planet. I got also some experiences with creating dishes with that egg.
This is a quick question unrelated to the recipe but I NEED to know!!! Where did you get that beautiful flower bowl? I need it in my life!
PS: Omg none of your recipes have ever failed me!!!! I LOVE JOC I keep coming back to try more recipes ☺️
Hi Angelica,
Thank you very much for trying many of Nami’s recipes and for your kind feedback!
The flower-shaped bowls were from Daiso 10 years ago. We don’t know if they still have it.