Dashi – Japanese Sea Stock

Dashi - Japanese Sea Stock

Dashi, or Japanese Sea Stock, is the primary broth used in Japanese cuisine. It forms the base for countless soups, stews and sauces.

In Japanese cookery, the term Dashi can simply refer to a stock made from seaweed, mushrooms, dried fish, or some combination of these. However, unless the type is actually specified, the bare term ‘Dashi’ means a stock made from two very umami-rich ingredients: Kombu Seaweed, and Katsuobushi, which is dried, smoked, and fermented Skipjack Tuna, or Bonito.

This very basic preparation is used in countless Japanese dishes including soups, hotpots, braised and simmered dishes, as well as a variety of sauces. It such a cornerstone of Japanese cuisine that it is almost possible to have had a multicourse meal in a Japanese restaurant without having had Dashi in one dish or another. You can buy Instant Dashi Soups Stocks to prepare it these days, but if you are interested in Japanese cookery on your own kitchen, learning how to prepare this important, but simple stock is essential.

Ingredient Notes for Dashi

If you are not entirely familiar with the two main ingredients for Dashi, please have a look at my Introduction to Kombu, and my Introduction to Katsuobushi.

In the introduction to Katsuobushi, you will note that the preserved fish can be purchased in many different forms, including shavings of varying thickness. Here, we will be using the finest, paper-thin sort, which is generally the most commonly available form.

How To Make a Japanese Sea Stock

Simmering Kombu for Japanese Sea STock

First, put the water and Kombu in a pot (you may need to cut the Kombu into pieces first) and soak for 30 minutes or so. Then, put the pot on a burner at moderate heat and allow it to come *almost* to a boil. Once you see small bubbles starting to rise, remove the Kombu and reserve for now.

Adding Katsuobushi to Boiling Kombu Water to make a full Sea Stock

Allow the Kombu simmering Water to come to a boil and throw in the Katsuobushi. Remove the pan from the heat and allow everything to cool for about 15 to 20 minutes until the shavings have mostly sunk to the bottom of the pot.

Katsuobushi Flakes after Boiling and Cooling.

 Once the sunken shavings are strained out (keep them for now), the resultant liquid is your Dashi. It can be used immediately or store in a covered container in the fridge for a week or so.

Ichiban and Niban Dashi

Making a Niban Dashi
Making a Niban Dashi

The first simmering of the main ingredients produces what is know as ‘Ichiban Dashi’, or ‘Number-One Dashi’. However, you can get a second run out them and produce a Number’ Two, or ‘Niban Dashi’.

Just add the leftover seaweed and fish to another 4 cups of water, bring it almost to a boil, and then simmer on low heat for 15 – 20 minutes. If you have used the very thin style katsuobushi shavings, the result will be quite a bit milder than the first run and some people add another handful or so of the fresh article to make up for this. Again, this can be used right away or stored for later use.

Using Dashi in Recipes

A Miso Soup, a classic use for Dashi

Miso Soup is something almost everyone has tasted if they have visited a Japanese Restaurant. The simple soup is present on virtually every Japanese Restaurant menu and is very popular. A good Dashi is the backbone of this soup, with Miso adding an additional Umami punch.

Beef and Vegetables being braised with Dashi

Dashi makes a great medium for braising all sorts of meats and vegetables and imparts delicious flavor. Here, Beef strips are braised with Potato and Broccolini in Dashi. This is an adaptation of a Japanese cookery technique and ingredient to an otherwise Western dish.

A Nimono of Pork and Daikon

This dish of Pork simmered with vegetables in Dashi is a classic Nimono style dish. Here, Fatty Pork is browned in fat. Daikon, carrot and shiitake strips are added and quickly sautéed, then Dashi added to barely cover. The dish is simmered fairly vigorously until only 1/3 of liquid remains (about 20 minutes), then blanched and chopped daikon greens are added for the last few seconds and all is served hot.

A Kakejiru Stock

A well made Japanese Sea Stock is the foundation of a more complex preparation called Kakejiru, which has many uses, but is especially favored as a noodle broth.

Mizuna Potato Nimono

Above, you can see a classic Japanese Mizuna Potato Nimono, in which Mizuna and Potato are simmered in Kakejiru until the Sauce is all but been slightly reduced.

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Dashi – Japanese Sea Stock

Dashi, or Japanese Sea Stock, is essential for preparing many dishes in Japanese cuisine. Read here to learn how to prepare it from scratch.
Course: Soup, Stock
Cuisine: Japanese
Keyword: Coconut Water, Kombu, Katsuobushi
Author: John Thompson


  • 4 cups water;
  • 1 8- inch piece of Kombu;
  • 2 good-sized handfuls of Katsuobushi shavings.


  • Soak the Kombu in the 4 cups of water in your cooking pot for about 30 minutes until softened.
  • Put the pot over moderate heat and allow the water to *almost* come to a boil.
  • Remove the Kombu and reserve.
  • Allow the water to come to a boil and then add the Katsuobushi flakes,
  • Immediately remove the pan from the heat and let sit for 15 to twenty minutes until the stock as cooled and the fish flakes have sunk to the bottom.
  • Strain your Dashi and use as needed.

Comments, questions or suggestions most welcome!