Kombu and bonitovlokken, that's all it takes to make dashiDashi is the basic stock of Japanese cuisine. You can make it in several manners, but mostly dashi is made with seaweed and dried bonito. Below there are several recipes for making dashi. The two main dashi's are ichiban dashi and niban dashi, otherwise known as dashi I and dashi II. Unlike Western stock dashi only needs little time to prepare. You just need two ingredients,; katsuoboshi (dried and smoked bonito flakes) and kombu (dried seaweed), and water.
Dashi I must always be made freshly, at the most a couple of hours in advance. Dashi II will keep up to three days in the refrigerator, and can be frozen. But the flavour will become less. Although I prefer not to use stock cubes, when needing only a tyablespon or two from dashi, I use instant dashi. When you are preparing a whole Japanese meal, it is handy to add up all the amounts of
dashi you'll need and make them in one go.
Because fish (the bonito) is used for making dashi, this is not a vegetarian stock. Buddhist monks in Japan have invented dashi made with shii-take mushrooms instead of bonito.
On the Dutch division of my site I have several Japanese recipes, you could try and translate them with the 'Translate'-button in the navigation menu.

Why the difference between dashi I and dashi II?

Dashi I has a subtle favour and is used for elegant, clear soups which are served as one of the first courses in an elaborate menu.
Dashi II is more robust, is used for sauces and miso soup. Miso (a kind paste of fermented soy beans) has a very recognizable odour and taste (I like it). The triad rice-miso soup-preserved vegetables is the basis of the Japanese meal. In a menu with more courses, this triad is served last, before dessert (if any).
If you only need a few tablespoons of dashi II for a sauce, you can use instant dashi (like Western stock cubes), or your own frozen ice cubes of dashi II.

The Japanese cuisine has several dishes with the so called 'fifth flavour'. In Western cuisine there is sweet, sour, salt and bitter. But how to describe the taste of truffles? They taste umami. Umami is a Japanese phrase meaning something like bliss, deliciousness. Well-made dashi, whether made with katsuoboshi or shii-take, also exudes umami.

Useful trick
Important when you strain dashi:mUse two strainers with a cloth or kitchen paper between them. The cloth or paper won't be clogged, if you use cloth it will be easier to clean, and most important when you want to re-use kombu and bonito for dashi II: you can easily remove them from the upper strainer.
See my page on chopsticks to find out how to eat your soup with sticks.

Dashi recipes Print this recipe

Ichiban dashi (dashi I)
1 liter(4 cups) cold water
10 gram (1/3 ounce) kombu (dried hard sheets of seaweed)
15 gram (1 cup) katsuoboshi (dried flakes of bonito)
Preparation: Wipe kombu with kitchen paper, put it in a pan. Add water, bring slowly to the boil. Take the kombu out of thewater just before it starts boiling. Add all katsuoboshi, bring the water to the boil once more, then immediately take the pan off the fire. The bonito flakes will swell. After five minutes, stain the dashi through a sieve with a fine-meshed cloth or paper towel.
Do not discard kombu and katsuoboshi, you may need it for making dashi II.
Niban dashi (dashi II)
Method a, when making dashi I:
1,5 liter (6 cups) cold water
kombu and katsuoboshi from dashi I
10 gram (2/3 cup) new katsuoboshi
Preparation: Return kombu and katsuoboshi that you've used for making dashi I to the pan. Add cold water, bring to the boil, let simmer until the water has been reduced to 1 litre. Add the second batch of katsuoboshi, take the pan off the fire, strain the dashi II after five minutes through a sieve covered with kitchen paper or cloth.
Niban dashi (dashi II)
Method b, if you do not need any dashi I:
1,5 liter (6 cups) cold water
10 gram (1/3 ounce) kombu
15 gram (1 cup dry) katsuoboshi
10 gram (2/3 cup) new katsuoboshi
Preparation: Proceed as if making dashi I, but let the dashi simmer for twenty minutes after adding the first batch of katsuoboshi. Then add the second batch, take the pan off the fire, strain the dashi II after five minutes through a sieve covered with kitchen paper or cloth.
This is a good method when you don't need dasi I. But if you do, please use the recipe below.
Vegetarian dashi
1 liter (4 cups) cold water
10 gram (1/3 ounce) kombu
15 gram (1 cup) dried shii-take
Preparation: Wipe kombu with kitchen paper, put it in a pan. Add water, bring slowly to the boil. Take the kombu out of thewater just before it starts boiling. Add dried shii-take mushrooms, let stand for fifteen minutes. Strain the niban dashi through a sieve covered with kitchen paper or cloth.
The shii-take can be used afterwards in other recipes.
Kombu dashi (also vegetarian)
15 gram (1/2 ounce) kombu
1 liter (4 cups) cold water
Preparation: Wipe Veeg de kombu with kitchen paper. Put in a bowl with cold water, let stand for a whole night. This dashi is not boiled.

Soup for Japanese noodles

Noodle soup is made with two components, dashi and a flavouring called tare no moto. All you have to do is mix them. For hot noodle soup the proportions tare no moto/dashi are 1 to 6. For cold noodles the proportions are different, tare no moto/dashi is 1 to 4.

How to prepare dashii is explained above. The second component of noodle soup, tare no moto, consists of soy sauce and mirin (zsweet rice wine) with sugar. This mixture has to 'mature' fior at least twelve hours before use, and will keep for a week.

1,2 deciliter (1/2 cup) soy sauce
1,2 deciliter (1/2 cup) mirin (sweet rice wine, not the same as sake)
2 Tbsp sugar
salt (optional)

Heat soy sauce and mirin in a small pan, add sugar as soon as it boils. Lower the heat, and stir with a wooden spoon until it boils again. Let it cool without a lid. Then keep in a closed container in the refridgerator fot at least twelve hours.
With 8,5 dl (3 1/3 cup) dashi enough for 1 liter (4 cups) kake-jiru to serve with hot noodles. 
With 3,5 dl (1 1/3 cup) dashi enough for 1/2 liter (2 cups) tsuke-jiru to serve with cold noodles.

All descriptions of ingredients

Bonito shavingsKatsuobushi - Dried, fermented and smoked bonito tuna. The fish has become rock hard in the proces, and has to be shaved before use with a special instrument resembling a wood plane. Because this is hard work, you can buy katsuobushi shavings in packages.
Kombu kelp - Also named konbu. An edible kelp from several members of the Laminaria family. The seaweeds grows in leaves that are several metres high, reaching up to the light. When kombu is dried, it forms hard sheets. Never rinse komby, just wipe it clean with a paper towel.
Mirin - Sweet Japanese cooking rice wine. Opened bottles keep long. Sweet sherry is not really a substitute, thick syrup is better.
Shii-take - A mushroom that is indigenous to Asia, scientifically known as Lentinus edodes. It grows on decaying wood. Their structure is meaty, and they are very tasty. The stalks are too hard to use, you could use them in soup (but remove the stalks before serving). Shii-take have been cultivated in China since the fourteenth century, in Japan since the seventeenth century. Cultivation took no less than three years. But when it became commercially feasible to cultivate them they are easy to come by.
Soy sauce - There are many different kinds and qualities of soy sauce. The fundament is fermented soy beans and wheat meal, and salt. Japanese soy sauce is a thin, clear liquid, ranging from darkish red ('light') to black in colour.

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