Need a family meal ready in under 20 minutes? Try this quick and easy Japanese Ketchup Spaghetti, known as Napolitan. Home cooks all across Japan prepare this simple recipe that elevates pantry staples with fresh ingredients like sausages, mushrooms, onion, and bell pepper. It’s a savory and satisfying dish!
Ketchup in spaghetti?! You hear it right. The idea of spaghetti with ketchup sauce may make any Italian cringe. However, Japanese Ketchup Spaghetti, or what we call Spaghetti Napolitan (スパゲッティーナポリタン), has been a popular menu at cafe restaurants (Kissaten) since the 1950s. This comforting pasta dish always brings a nostalgic memory to many Japanese who grew up eating it.
Table of Contents
What is Napolitan?
Napolitan is tomato ketchup-based, Japanese-style pasta that consists of spaghetti noodles, onions, green bell peppers, button mushrooms, and Japanese sausages. There are a few variations where we replace the sausages with bacon or ham. However, in general, it all has a standard sunny look of appetizing orange.
Phonetically, the Japanese language doesn’t distinguish R and L as separate sounds. For that reason, it uses the same katakana characters to represent R and L sounds of Western alphabets. So we write it as either Napolitan or Naporitan. While the spelling “Naporitan” is derived from romanji (the romanization of Japanese), the spelling “Napolitan” takes the origin of the name (Napoli) into account.
The Origin of Napolitan
There are a few theories of how Napolitan originated. The strongest theory is that it originated in Yokohama during the postwar era.
Around the 1950s, the head chef at the New Grand Hotel in Yokohama created this recipe after being inspired by the spaghetti and tomato sauce dish served to the American military. Since tomato sauce was a rare ingredient at that time, he used ketchup as a substitute for pasta sauce. He then named it “Spaghetti Napolitan”, or Napoli, after Naples, Italy.
Around the same time, Japan started to open itself to the world and began to consider fashionable new ideas from the West. These newly Westernized dishes like Spaghetti Meat Sauce and Spaghetti Napolitan received excellent responses. Eventually, they became mainstays in the cafes and Japanese home kitchens. To this day, the two dishes are still two of the most popular pasta dishes among Yoshoku (Western-influenced food, 洋食) in Japan.
Ketchup as The Key Flavoring
Not surprisingly, Japanese cuisine has used ketchup in seasoning various dishes, as this all-star American condiment lends a depth of flavor with its sweet-tangy profile.
Therefore, you can find ketchup used in Japanese Curry, Omurice, Ebi Chili, and a pasta dish like Spaghetti Napolitan. It’s a great example of how open we are when it comes to adapting other cultural influences in improving our own cuisine.
Why You’ll Love This Pasta
The genius about Spaghetti Napolitan is that it utilizes most of the pantry staples in your kitchen. The common ingredients include onion, mushrooms, green bell peppers, and sausages (ham or bacon). It’s seasoned with ketchup and Parmesan cheese and served with Tabasco sauce.
It’s really flexible, too! For example, you can try bacon in place of sausage. Likewise, use peas in place of bell peppers. Top it with a fried egg if you’d like. But simplicity is good for this recipe. When you don’t have any of the ingredients in the recipe, you can throw in whatever happens to be in season or on-hand in your kitchen.
To make it vegetarian-friendly, leave out the meat and add more mushrooms. Mix it up with a different type of mushroom for texture and flavor.
This dish is really easy to make and the flavor is kids-friendly. It makes an ideal meal for a quick dinner if you have a family with young children. I remember my son used to request this Ketchup Spaghetti when I asked what kind of pasta he would like for lunch.
Cooking Tips
- Timing is key for a smooth workflow. Get your prep work done while you boil the water to cook the spaghetti. You should have the cooked ingredients and sauce ready by the time the spaghetti is done cooking. Then toss everything together and serve!
- The taste of ketchup slightly varies depending on the brand. I usually use this organic ketchup (No GMO ingredients, no high-fructose corn syrup) but a similar one would work great. Napolitan does have a slightly sweet taste to it, but feel free to omit the sugar as listed in the recipe. For the authentic flavor, get a bottle of Kagome Tomato Ketchup from the Japanese grocery store. It is the classic Japanese ketchup to make Omurice and Napolitan.
- Always reserve the pasta cooking water. Set aside ¼ cup (or more depending on the serving portion) of the pasta cooking water. The starch in this salty pasta water acts as a binder and creates an emulsion when you add it to a sauce that contains fat like butter or oil.
- Don’t overcook the spaghetti as you will continue to cook a bit more in the frying pan.
- Consider textures. In my opinion, this pasta dish tastes best with various textures. For veggies such as bell peppers or fresh peas or sugar snap pea, I’d keep them on the crunchy side. However, my kids do not like raw or undercooked bell peppers so they always ask them to be as thin and wilted as possible. I personally like to cook the onion a bit more (no need to caramelize) to get the sweet flavor out of it.
- Just a tablespoon of butter at the end adds umami and creaminess to the dish. So don’t skip it!
It cannot be easier to put this Spaghetti Napolitan together! For a fancy yet effortless weeknight dinner, serve it with a green salad and wine. Enjoy!
Other Japanese-Style Pasta Recipes
- Miso Butter Pasta with Tuna and Cabbage
- Creamy Mushroom and Bacon Pasta
- Ume Shiso Pasta
- Japanese-style Pasta with Shrimp and Broccolini
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Napolitan (Japanese Ketchup Spaghetti)
Video
Ingredients
For the Sauce Seasonings
- ⅓ cup ketchup (for an authentic flavor, use Kagome Tomato Ketchup from the Japanese grocery store)
- ½ Tbsp milk (optional; for a creamier taste)
- 2 tsp Worcestershire sauce
- 1 tsp sugar (optional; for an authentic Japanese taste)
For the Sauce Ingredients
- ½ onion (3.5 oz, 100 g)
- ¼–½ green bell pepper (2.5 oz, 70 g)
- 4 mushrooms (2.5 oz, 70 g)
- 5 oz sausages (I use 4–6 kurobuta or arabiki sausages from the Japanese market; you can substitute another type of sausage, ham, bacon, etc.)
- 1 Tbsp extra virgin olive oil
- 1 clove garlic
- ¼ tsp Diamond Crystal kosher salt
- ⅛ tsp freshly ground black pepper
For the Pasta
- 7 oz spaghetti
- 1½ Tbsp Diamond Crystal kosher salt
- ¼ cup reserved pasta water (you may not need it; check your sauce and add gradually)
- 1 Tbsp unsalted butter
For Serving
- 2 Tbsp Parmigiano-Reggiano or Parmesan cheese
Instructions
- Gather all the ingredients. Start boiling a large pot of water (I use a 4 QT pot).
To Prepare the Ingredients
- In a small bowl, combine ⅓ cup ketchup, ½ Tbsp milk, 2 tsp Worcestershire sauce, 1 tsp sugar. Mix them together and set aside.
- Cut ½ onion into thin slices.
- Cut ¼–½ green bell pepper in half crosswise (if it‘s long), and then cut into thin strips.
- Cut 4 mushrooms into thin slices.
- Cut 5 oz sausages diagonally into thin slices.
To Boil the Spaghetti
- Once the water is boiling, add 1½ Tbsp Diamond Crystal kosher salt and 7 oz spaghetti. Stir to make sure the noodles don‘t stick to each other. Cook the spaghetti according to the package directions. Toward the end of cooking, reserve some pasta cooking water.While the pasta is cooking, prepare the sauce.
To Cook the Sauce
- Heat a large frying pan over medium heat. When it‘s hot, add 1 Tbsp extra virgin olive oil and distribute it evenly. Crush and add 1 clove garlic (I use this garlic press) and sauté for 1 minute, just until golden and fragrant.
- Add the onions to the pan and sauté for 2–3 minutes.
- When the onions are wilted, add the sausages and sauté for 1 minute.
- Add the bell peppers and mushrooms and sauté until everything is cooked.
- Season with ¼ tsp Diamond Crystal kosher salt and ⅛ tsp freshly ground black pepper.
- Push the ingredients to one side and add the sauce mixture to the empty side of the pan. When the sauce starts to bubble and thicken, mix it together with the sausages and vegetables.
- Now, scoop out some of the starchy cooking water from the pasta pot, about ¼ cup reserved pasta water. Remember, you may not need the reserved pasta cooking water that you saved. Add it to the pasta sauce only if it needs to loosen up. At times, I do not use it at all or use 1–2 Tbsp. Check the consistency of the sauce, and gradually add reserved pasta water, stirring well, until the sauce is the consistency you like.
- Mix it all together and let the sauce simmer and reduce a bit.
- By now, the spaghetti should be done cooking. Drain it well in a colander and add it to the pan with the sauce. Add 1 Tbsp unsalted butter and toss to combine using tongs, making sure the sauce coats the pasta evenly.
To Serve
- Serve the Napolitan immediately on individual plates. Shave 2 Tbsp Parmigiano-Reggiano or Parmesan cheese over the pasta now or at the table.
To Store
- You can keep the leftovers in an airtight container and store them in the refrigerator for 3 days or in the freezer for a month.
Nutrition
Editor’s Note: This post was originally published on Apr 19, 2013. The post has been republished with updated content, new images, and a slightly-revised recipe on July 25, 2022.
After watching lots of anime my husband mentioned that all the Napolitan pasta he sees being eaten in anime was making him really crave it so I was happy to find this recipe. This is really good. Used sweet Italian turkey sausage and red and yellow bell peppers. He asked if I’d make it again so I guess he agrees it tastes as good as the anime pasta looks. 🙂 Looking forward to some leftovers tomorrow!
Hi Geri! Awesome! We are glad to hear you and your husband enjoyed Napolitan! 🥰
Thank you very much for trying Nami’s recipe and sharing your cooking experience with us!
Looking forward to trying this recipe. The idea of ketchup and speghetti is not something I am used to but this recipe looks good.
Hi Mandy! Thank you very much for reading Nami’s post!
We hope you will give this recipe a try! The new flavor might surprise you!😉
I made a version of this awhile back, mostly out of curiosity for what a ketchup-base sauce would taste like. It was good! Cooking ketchup changes the flavor somehow and really makes it a worthwhile ingredient in serious cooking.
Hi Phil! We are glad to hear you enjoyed the Ketchup Spaghetti!😊
Thank you very much for sharing your cooking experience with us!
I visited family in Okinawa. While I was there, my cousin made this. I thought…ketchup??!! No way! But, it turns out that it is DELICIOUS!! So glad to have the recipe now. Thank you for sharing!
Hi Noriko! This dish is surprisingly delicious!😁Right?!
Thank you very much for reading Nami’s post and for your kind feedback!
Hello, Nami!
I first heard of this dish while watching some baseball-themed anime and wanted to try it. Thank you for sharing this recipe!
Unfortunately, in Russia I never saw it in the menu of any Japanese restaurants and cafes. Tried this one out and love it very much)
Hi Tonya! We are so happy to hear you tried this recipe and over it!😊 Thank you very much for your kind feedback!
There’s a place in Houston called House of Bowls that serves a version called “House Special Spaghetti” with bacon, peas, carrots, and topped with a fried egg… really good!
Hi Sean,
With bacon!😋 Yum! Thank you for your input!
Can you make this dish called: Omlet Spaghetti Napolitan (Neapolitan) is a new Japanese-style Pasta (Omurice style pasta)?
I seen on a YouTube video titled: Omlet Spaghetti Napolitan (Japanese-style Pasta) Restaurant Loved by Local Japanese #229 – Rion Ishida YouTube Channel
Omlet Spaghetti Napolitan (Neapolitan) is a new Japanese-style Pasta (Omurice style pasta)! The dish consists of Spaghetti, tomato ketchup, onion, green peppers and sausage covered by super fluffy egg.
Hi Joe!
We currently don’t have the recipe on the site.
We’ll make sure to add the recipe to Nami’s list. Thanks for your request! 😊
Hi Naomi!
I made this dish for lunch, and I have to tell you how tasty it was. Even my other half complimented me on the taste. Thank you for generously sharing your recipes and methods so freely and professionally. Happy Thanksgiving to you and your family.
Terry
Hi Terry!
Thank you very much for trying this recipe and for your kind feedback.
We are glad to hear you enjoy this dish. Happy Thanksgiving to you and your family too!
Nice recipe. I liked the addition of sugar and Worcester sauce with the ketchup.
Some reciples call for butter. I think it needs something to counteract the ketchup so I used two tablespoons of margerine at the end and stirred into the pasta and sauce. Topped with parmesan and olive oil. I want to serve to an Italian to drive them crazy.
Hi James!
Please let your Italian friend know that this is a Japanese style pasta dish!😉
While I’m not a fan of Napolitan, I have eaten my fair share of it while living in Tokyo, it’s not bad. I however do know a lot of people that look down on it for it’s rather plebeian nature. But when you get down to it, it’s tomatoes, spices and sugar. Three things that have a place in pasta sauce.
Hi Rick! Thank you for sharing your thoughts and I like your thinking! 🙂
Delicious. Will definitely cook it again!
Hi Alice! Thank you for your kind feedback. So happy to hear you liked this recipe!
Whipped this up quite quickly for dinner. The mushrooms, onions, capsicum, and sausage work really well together with the tomato sauce. I added a bit extra Worcestershire sauce – I’m very bad at pronouncing it, but I love Worcestershire sauce! Very simple to make.
As always, thanks Nami!
御馳走様でした!
Hi Julia! I’m so glad to hear you enjoyed this recipe. Me too, I can’t pronounce. The Japanese way of pronouncing this name is much easier though – ウスターソース. 😀
When I was a kid my Japanese mother would make spaghetti with ketchup and I thought that she just don’t know that spaghetti needed to be topped by the sauce out of a jar. Little did I know that it was a Japanese style of cooking. I love thia recipe as it is super easy and tasty and it reminds me of my childhood.
Hi Kathy! Awww! Thanks for sharing your story! She probably feels very nostalgic about the taste. I do want to make these once in a while. It’s something we ate a lot growing up as it was a part of kids’ meal (Okosama Lunch) t restaurants often. 🙂
Love napolitan and this easy recipe! Thanks for sharing I’ll try it tonight! One question I always encounter with all Japanese recipe that uses Worcestershire sauce. Everytime I follow to add Worcestershire sauce it always turns out too tangy even when I add a little. Is there a difference between the Worcestershire sauce sold in North America vs Japan? Thank you.
Hi Ritsuko! I’m sorry for my late response. You probably made it already. 🙁 Japanese Worcestershire sauce are slightly sweeter, so I usually recommend adding a bit of sugar if you use western one (especially if the amount is a lot). If it’s a little bit, I won’t worry too much – it’s just the hint of the taste, not the main taste.
This sounds very much like the spaghetti I have bought from the ready-made section at the Mitsuwa Marketplace we frequent. Only they use hot dogs. One dish my mom made when I was growing up was spaghetti (with a can of tomato soup for the sauce) and hot dogs. I’ve been craving that – and the Japanese spaghetti I get up at Mitsuwa. I’ll have to make this recipe!
Hi Linda! Thanks for sharing your story with us! Love reading/hearing about food memory and story like this! Hope you enjoy this recipe, Linda!