Bonito and Kombu Dashi Recipe
From 'Japanese Home Cooking' by Sonoko Sakai

Simmering bonito flakes to make dashi. (MIXA/Getty Images)
Bonito and Kombu Dashi
By Sonoko Sakai
This combination of bonito flakes and kombu makes the most popular and flavorful all-purpose dashi. The idea is to extract the flavors by steeping the ingredients for the first round of dashi, which is called ichiban dashi, or "number 1 dashi." The amount of bonito flakes I use for this recipe depends on how I will use the dashi. For everyday dashi, I make a medium-strength dashi using 3 cups (20 g) bonito flakes. When I make noodle soups, I want a stronger dashi, so I use 4 cups (30 g) bonito flakes. This dashi is enjoyed for its fragrance and is so flavorful on its own that you can drink it straight, like soup.
5 cups (1.2 L) filtered water
1 piece kombu, about 3 x 3 inches (7.5 x 7.5 cm)
3 to 4 cups (20 to 30 g) bonito (dried skipjack tuna) 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 or a 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.
Yield: about 4 cups (960 ml)
Note: You can reuse the bonito flakes and kombu to make one more pot of dashi. Add the bonito and kombu to 3 cups of water. Bring to a boil and simmer for 5 minutes until the volume is reduced by half.
From Japanese Home Cooking by Sonoko Sakai. © 2019 Sonoko Sakai. Photographs © 2019 by Rick Poon. Reprinted in arrangement with Roost Books, an imprint of Shambhala Publications, Inc. Boulder, CO.