What Is Dashi? And How to Use It

Rich, fragrant and chock-full of umami flavor, dashi is an essential part of Japanese cooking. The term refers to a group of savory stocks that form the basis for many Japanese dishes, including soups, sauces and seasonings. Dashi can be made from a range of ingredients, including kombu, bonito flakes, and shiitake mushrooms, and it’s so ingrained in Japanese cuisine that many Japanese chefs spend years perfecting their dashi. 

“Dashi is very fragrant and deep with umami,” says cookbook author and educator Sonoko Sakai. “Dashi determines how skillful a Japanese chef is when he presents his dish because most authentic Japanese dishes have some kind of dashi-based seasoning. It’s not just in soup but throughout the course of the meal you will see dashi in salads, dashi in a hot pot, dashi in a simmered dish or a braised dish. It’s one of the essential seasonings, just like salt and pepper, olive oil or garlic.”

Here, learn about different types of dashi, how to make it, and how to use it in your cooking.

Types of Dashi

There are many types of dashi, but Sakai says the most popular one, which she uses for everyday cooking, is made with kombu (a dried seaweed in the kelp family) and katsuobushi (bonito flakes). Dashi is also commonly made with shiitake mushrooms, niboshi (dried sardines), dried scallops, or soybeans.

“There are many, many ways you can combine these ingredients to make a soup,” Sakai says. “So in a way, it's very universal, because when you make a western broth, you also put in onions and bones and carrots and celery. It’s not just one thing but a combination to deepen the flavor of the broth.”

How to Make Dashi

Although instant dashi powders are readily available, Sakai says to avoid them as they typically contain lots of additives. And luckily, making homemade dashi is quite easy. Think of it like making tea, as the dashi base—kombu, bonito flakes, or shiitakes, for instance—is simply steeped in warm or cold water to extract its essence. You can cold-brew dashi, which results in a more delicate broth, or brew it over low heat. Sakai makes her all-purpose dashi with bonito flakes and kombu, which are soaked in water at room temperature for three to 10 hours. Dashi gets stronger in flavor the longer you let it steep—a cold-brewed dashi should steep for at least 30 minutes, but for a more fragrant, robust dashi, let it sit overnight.

Here, Sakai shares a few different recipes for making dashi from her cookbook, Japanese Home Cooking: Simple Meals, Authentic Flavors.

Kombu Dashi

Makes 4 cups

1 piece of kombu, about 4 x 4 inches
4 cups filtered water

In a large bowl, soak the kombu in the filtered water for a minimum of 3 hours (to a maximum of 10 hours) at room temperature. Remove the kombu and use the liquid immediately, or store it in the refrigerator, where it will keep up to 1 week. This piece of kombu can be used one more time to make a secondary dashi.

Bonito and Kombu Dashi

Makes 4 cups

5 cups filtered water
1 piece kombu, about 3 x 3 inches
3 to 4 cups bonito flakes

Combine the water and kombu in a medium saucepan. Heat over low heat until bubbles begin to form around the kombu, 5 to 10 minutes. Remove the piece of kombu before the water comes to a boil. Bring the water to a boil, turn off the heat. Add the bonito flakes. Let stand for 2 minutes, without stirring, to steep the bonito flakes. To strain the dashi, pour the liquid through a fine-mesh sieve lined with cheesecloth or a paper towel. Do not press the bonito flakes while straining, as it will cloud the dashi. Use immediately, or cool completely and refrigerate for up to 4 or 5 days or freeze up to 1 month.

Niboshi and Kombu Dashi

Makes 4 cups

1 ounce niboshi (dried sardines), about 15 dried sardines
1 piece kombu, about 1½ x 3 inches
5 cups filtered water

Snap off the heads and remove the insides of the sardines with your fingers. They will be dried and brittle, so they won’t be hard to clean. You can also buy cleaned sardines without the head and entrails. Place the cleaned sardines in a bowl, add the kombu and filtered water, and place in the refrigerator, covered, overnight. For a light cold-brew dashi, strain the liquid. You can use this liquid in your cooking. For a stronger dashi, transfer the liquid with the sardines and kombu to a medium saucepan and set it over high heat. When bubbles begin to form around the kombu, remove it from the liquid. Lower the heat to maintain a simmer and continue cooking for another 7 to 8 minutes. The liquid will turn a light amber color. Skim off any surface impurities, then strain the liquid through a sieve lined with cheesecloth or a paper towel. Discard the spent fish. You can reuse the kombu to make one more pot of dashi.

Recipes reprinted with permission from Japanese Home Cooking: Simple Meals, Authentic Flavors published by Shambhala Publications, Inc.

How to Store Dashi

Sakai says she always has dashi on standby, making a pot weekly and keeping it in a quart container in the fridge for easy use. Dashi can be stored in a sealed container in the refrigerator for up to a week or in the freezer for up to a month.

How to Use Dashi

Dashi is an incredibly versatile ingredient. It adds depth of flavor to most soups—including, of course, miso soup—but that’s just the beginning. Sakai says to use it anywhere you’d use chicken broth or stock, such as in recipes for classic minestrone, risotto, and even chili. She says a little bit of dashi also works great in salad dressings, as in ohitashi, a Japanese side dish often made with spinach.

“I think it's really an incredible broth to incorporate into your everyday cooking,” she says. “Why run to the store and buy a mediocre commercial broth when you could just make something fresh? It really improves the flavor of most of my dishes. I have never found a dish that it doesn't work for.”