Japanese Seasoning Soy Sauce
By infusing soy sauce with a few ingredients, you can make a seasoning soy sauce that combines some of the most commonly used flavors in Japanese cuisine into a single versatile sauce. It's known as Dashi Shoyu (だし醤油) in Japan, and its an easy way to add the smoky aroma and umami-rich taste of Japanese dashi stock to any dish without having to make the broth every time. Use it as an all purpose seasoning for stir-fried vegetables, noodle dishes, or any type of broth.
Table of contents
Why This Recipe Works?
- A small amount of sugar mellows out the salty soy sauce.
- By infusing the soy sauce with konbu and katsuobushi, you're adding umami to the soy sauce along with the marvelous flavor of dashi.
- Bringing the soy sauce to a boil with the other ingredients has the upside of eliminating the naturally occurring alcohol in the soy sauce, but it can also extract some undesirable flavors from the katsuobushi and konbu. It's kind of like the difference between cold brew vs. hot brewed coffee. That's why I prefer doing a cold infusion.
Ingredients for Dashi Seasoning Soy Sauce
- Soy sauce - Any Japanese soy sauce like Kikkoman will work, but a traditionally brewed soy sauce made from soybeans and wheat will taste best.
- Katsuobushi - Katsuobushi is skipjack tuna (sometimes translated as bonito) that's been fileted, cooked, and smoked for several weeks until it's dry and hard. Higher-grade katsuobushi is then inoculated with Aspergillus glaucus, a type of filamentous fungus, and sun-dried. Like anything, you tend to get what you pay for. Cheaper katsuobushi are sometimes blended with mackerel, includes a lot of bloodline, and they don't undergo the extra drying and fermentation. More premium katsuobushi, such as honkarebushi, has gone through the drying and fermentation process at least three times, which can take months.
- Konbu - In the same way that the growing conditions of plants can affect their taste, konbu (also sometimes spelled kombu) is affected by the conditions of the water in which it was grown. Hokkaido in the north of Japan is said to produce the best konbu, but it's a big island, and different regions produce konbu with wildly different flavor profiles. Rishiri in the north produces konbu that is mild and mellow in flavor and produces clear, delicate broths. This is why it's used in fancy Japanese cuisine. Hidaka on the southern side of Hokkaido tends to produce softer konbu than in other regions. It doesn't have a ton of umami, though, which is why it's used more for eating than making dashi. My personal favorite is konbu from Rausu in the east, which makes dashi with TONS of umami and a bold meaty flavor. If you can't find konbu, you can substitute flavor enhancers such as yeast extract or monosodium glutamate (MSG).
- Sugar - This is not necessary, but adding a little sugar to the soy sauce balances out the saltiness of the soy sauce. It also makes the dashi soy sauce easier to use because it eliminates the need to add sugar to the dish.
How to Make Japanese Dashi Soy Sauce
The first thing you want to do is dissolve the sugar in the soy sauce. How much sugar you add is up to you, but the added sweetness mellows out the saltiness of the soy sauce, and you can adjust this to taste.
Add the konbu and katsuobushi to the soy sauce and then cover and let the soy sauce infuse for at least twenty-four hours.
When the dashi shoyu is done, remove the konbu and set it aside. Strain the mixture through a tea strainer to remove the katsuobushi, and press on the solids to get as much soy sauce out of it as possible.
The resulting sauce can be stored in the refrigerator for a few months.
To upcycle the spent konbu and katsuobushi, slice it up and stir it into hot rice or use it as a filling for onigiri.
Other Japanese Seasoning Recipes
Japanese Seasoned Soy Sauce can refer to several different condiments, but it's most commonly Dashi Shoyu or dashi-infused soy sauce.
Japanese Seasoning Soy Sauce is a 4-syllable name pronounced as follows (read the italicized parts).
da like dot
shi like sheet
sho like show
yu like you
This recipe includes katsuobushi, so it is pescatarian but not vegetarian or vegan. You can substitute dried shiitake mushrooms for the katsuobushi to make a plant-based variant of this. The flavor will be quite different, but it will still have a ton of umami.
Because this seasoning is essentially concentrated dashi and soy sauce, it can be used to add a fuller flavor to all sorts of dishes in the convenience of a single sauce. Japanese noodle soups such as soba, salads such as ohitashi, and stews like Kabocha no Nimono are just a few of the cooking possibilities, but this soy sauce is also fantastic drizzled over tofu or as a dipping sauce for sashimi. Dashi shoyu is also also a great to way to add the rich taste of dashi broth to marinades.
- 1 cup soy sauce
- 2 teaspoons evaporated cane sugar
- 4 grams konbu
- 8 grams katsuobushi
- Stir the sugar into the soy sauce until it dissolves.
- Add the konbu and katsuobushi to the soy sauce, cover, and refrigerate for at least 24 hours to infuse the soy sauce.
- Remove the konbu and pass the soy sauce through a fine mesh strainer, pressing on the solids. Store the dashi soy sauce in a bottle in the refrigerator.
Kathy Stroup says
Thank you for explaining another Japanese condiment. I have seen bottles of this in stores, but I never knew what it was, or how it was used. Great to know! I always like making homemade sauces since I can adjust them to my personal tastes. This should be great to have around for Noodle Soup Season!
Thanks also for showing us how to use the katsuobushi and konbu after it's infused. Takes the sting out of the price tag if I can get another dish out of them. Could you freeze them if you don't have a use for them right away?
Marc Matsumoto says
Hi Kathy, glad I could show you something new 😄 For noodle soups, it's best to use mentsuyu https://norecipes.com/mentsuyu-japanese-noodle-soup-base/ which has a slightly different balance of flavors, but this will certainly work in a pinch!
The spent konbu/katsuobushi has a high enough salt content that it should last for a while in the fridge, but if want to keep it for longer, freezing it is a great idea!
It is steeping in my fridge for the next 2 days, & I can't wait to try it. Thank you, Marc!!!
Marc Matsumoto says
Wow that was quick! I hope you enjoy it😄
I don't have much of a sweet tooth, but I'm really sensitive to the types and grades of various sugars (and salts). Evaporated cane sugar (which I'd strangely never used until Marc introduced me to it) has pretty drastically improved every dish I make with it from teriyaki to dashi shoyu...to cocktails! Thanks again, Marc. These are the little details that really boost one's game in the kitchen (and bar!)
Marc Matsumoto says
Hi DJ, thanks for sharing! I'm happy to hear you've enjoying evaporated cane sugar. It's my go-to sugar in the kitchen for most recipes because it adds so much more flavor than the white stuff, but it's not as overpowering as brown sugar (most brown sugar in the US is just white sugar with molasses added back in anyway). If you have a chance to find it, I'd recommend trying out kokutou. It's Japanese brown sugar and has a really nice caramel flavor. It has a fairly strong taste so it can't be used in everything, but I like making a simple syrup from it and using it in cocktails.