Basic Sea Stock


Preparation info

  • Difficulty


  • Makes

Appears in

An Ocean of Flavor: The Japanese Way with Fish and Seafood

An Ocean of Flavor

By Elizabeth Andoh

Published 1988

  • About

Most soups and simmered dishes in Japan are based on a sea stock. This classic version calls for only two ingredients— kombu (kelp) and katsuo bushi (fish flakes). Unlike so many stocks that take hours of slow simmering, this sea stock takes just a few minutes to make. Timing is crucial here: Just as the water comes to a boil, the kelp gives forth its delicate salty-sweet taste, and moments after the fish flakes have been added to the hot kelp broth, they release their smoky flavor into the stock. Strained immediately at its peaks of flavor, the stock is clear and delightful.

Since dashi loses its delicate aroma and subtle flavors when frozen, it’s best to make it fresh when you need it. Leftover stock will keep well for 4 or 5 days in the refrigerator.


  • cups cold water
  • 20 square inches dashi kombu (kelp for stock making)
  • 1 packet (5 grams) or cup loosely packed katsuo bushi (dried bonito flakes)


  1. Place the kelp in a 2- to 3-quart pot. Add the water, and over high heat, rapidly bring it just to the point of boiling.
  2. Remove the pot from the burner, and sprinkle the bonito flakes over the surface of the water. Let the broth stand for 2-3 minutes, until the flakes begin to sink.
  3. Remove the kelp with tongs or chopsticks, and strain the broth immediately through a cloth- or paper-lined colander.

Save the kelp after making stock as it can be recycled in several ways: Kelp added to the water used when cooking rice will add a depth of flavor, especially if the rice is being seasoned later to make sushi (see shari). Softened kelp can also be cooked as a vegetable; it tastes somewhat like fennel or anise (see Fancy Kelp Knots).

Softened kelp can be kept for a week to 10 days if you do the following: (1) Rinse it under cold water immediately after removing it from the stockpot. (2) Drain the kelp and pat it dry on paper towels. (3) Store the kelp in a closed glass container or plastic bag. (4) Keep it in the vegetable compartment of your refrigerator.