Learn how to make Kombu Dashi, vegan-friendly Japanese soup stock, at home and create the umami flavor for your Japanese dishes!
Last time when I shared the recipe for Japanese dashi stock, it was a combination of kombu and katsuobushi called Awase Dashi. Today I’m sharing Kombu Dashi recipe, which is the vegetarian and vegan-friendly version.
What is Kombu Dashi?
Dashi (だし) is Japanese stock and is used in many Japanese dishes as the basic flavoring purpose. It is typically made from the following ingredients:
- Kombu (kelp)
- Katsuobushi (dried and smoked skipjack tuna that is shaved into thin flakes)
- Iriko or niboshi (anchovy/sardine)
- A combination of all or two of them.
The umami from these ingredients yields a great depth of soup stock that very little flavoring is required when you season the food. The wonderful thing about kombu dashi is that it is vegetarian and vegan-friendly and the easiest dashi you can make.
What is Kombu?
Kombu (昆布 konbu) is an edible kelp that is used extensively in Japanese, Korean and Chinese cooking. In Korean, it is referred to as dasima 다시마, and in Chinese as haidai 海带.
This sea vegetable earns its name as ‘the king of seaweeds’ because it possesses an amazing flavor and nutritional value, unlike any other seaweed. The most noteworthy advantage is its high content of glutamic acid, an amino acid responsible for umami. And umami is what you’re looking for in a dish where it provides a complex, elemental taste.
If you follow a vegetarian/vegan diet or simply want to embrace a more plant-based diet, kombu is an outstanding ingredient to incorporate into your cooking. Besides being a great flavor enhancer and tenderizer, kombu is a powerful, health-promoting food that can make up for certain nutrients that are absent in the diets.
In my Pantry Kombu page, I discuss different types of kombu and which kombu is good for specific types of food. Please go over the post if you want to know more about how to use kombu for Japanese cooking.
A few quick tips on cooking with kombu:
- There is no need to wash or wipe off the white powdery substance as kombu is pretty clean these days. The white compound is known as Mannitol which is the key contributor to the umami.
- Make a couple of slits on the kombu will help release more flavor.
- Do not throw away the leftover kombu as it is can be repurposed into Kombu Tsukudani (simmered kombu) or Homemade Furikake (rice seasoning).
Two Methods in Making Kombu Dashi:
1. Cold Brew Kombu Dashi (Mizudashi 水出し)
This method is pretty hands-off. All you need is to put water and 1-2 kombu strips in a large bottle, let steep for 2-3 hours or more.
2. Hot Brew Kombu Dashi (Nidashi 煮出し)
If you need dashi right away, this is the method you can go with. Just place the kombu and water in a medium pot and gently bring out the flavor. Turn off the heat before it comes to a boiling point.
Recipes Using Kombu Dashi
If you can’t access to kombu, another delicious option for making another vegetarian/vegan dashi is Shiitake Dashi.
Japanese Ingredient Substitution: If you want to look for substitutes for Japanese condiments and ingredients, click here.
Learn how to make Kombu Dashi, Vegan-friendly Japanese Stock, at home and create the umami flavor for your Japanese dishes!
- ⅓ oz kombu (dried kelp) (10 g, 4" x 4" OR 10 cm x 10 cm) (You can add more for stronger flavor)
- 4 cups water (roughly 1000 ml)
Gather all the ingredients. Most Japanese recipes would say to gently clean the kombu with a damp cloth. However, these days, kombu is pretty clean so just make sure it doesn't musty. DO NOT wash or wipe off the white powdery substance (Mannitol), which contributes to the umami flavor in dashi.
Make a couple of slits on the kombu, which will help release more flavor.
Put water and kombu in a large bottle.
Put the cap on and let it steep on the counter for 2-3 hours in the summertime and 4-5 hours in the winter time. If you don't plan to use it right away, you can start steeping in the fridge from the beginning.
Remove the kombu from the bottle and reserve the used kombu (see below). Kombu dashi is now ready to use. If you are not using the dashi right away, save it in a bottle and keep in the refrigerator for 4-5 days or in the freezer for 2 weeks. I recommend using it sooner for the best flavor.
In a medium pot, put the kombu and water. [optional] If you have time, soak for 3 hours or up to a half day ahead of time. Kombu’s flavor comes out naturally from soaking in water.
Turn on the heat to medium-low heat and slowly bring to almost boil, about 20-25 minutes.
Meanwhile, clean the dashi by skimming the surface.
Just before the dashi starts boiling, remove kombu from the pot (see below for what to do with it). If you leave the kombu inside, the dashi will become slimy and bitter.
Now kombu dashi is ready to use. If you are not using the dashi right away, save it in a bottle and keep in the refrigerator for 4-5 days or in the freezer for 2 weeks. I recommend using it sooner for the best flavor.
Save the used kombu in the airtight container for a few days in the refrigerator or for up to a month in the freezer. With the leftover kombu, you can make Kombu Tsukudani (simmered kombu) or Homemade Furikake (rice seasoning). I usually save the leftover kombu enough to make tsukudani.
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 and link to this post as the original source. Thank you.
Editor’s Note: This post was originally published in February 2013. The images have been updated in April 2019.