A full-bodied fish stock full of umami flavor that you can use in all kinds of recipes. Dashi is a basal stock used in many traditional and contemporary Japanese food recipes and sauces. It is made with only three ingredients: bonito flakes (dried, fermented and smoked skipjack tuna or bonito fish), kombu seaweed and spring water.
Cut a single sheet of kombu in half with scissors. Keep one half for future use. Hold the other half in your hand and cut strips across the width of the sheet of about 0,5 cm wide. Stop short at the end of the sheet so that the strips remain attached. The cutting alllows the water to fully permeate the kombu leaf. Keeping the leaf in one piece makes it easier to remove the sheet from the stock later on.
Put 1 liter (4 US cups) of spring water or mineral water without gas in a jug. Add the kombu sheet and leave it to infuse for 24 hours. The resultant stock will have a greenish tinge. It contains a high concentration of unami, which is vital for the taste of your dashi stock.
Pour the contents of the jug – including the kombu – into a saucepan and put in on a stove. Bring the stock to the boil and remove the kombu, for instance using a pair of metal tongs.
While the stock is boiling, add 10 g (1/3 oz) of bonito flakes. Once bubbles start forming, turn off the heat. Now push down the bonito flakes to fully immerse them in the stock. Use metal tongs or a wooden spoon, but do it gently and don’t stir. Bonito flakes are very fragile and tend to disintegrate easily. Leave the stock like it is for 15-20 minutes to infuse the flavors. The bonito flakes will gradually sink to the bottom.
Loosely cover a sieve with a cheesecloth and place it over a glass mixing bowl. Pour the stock from the pan into the sieve to filter out everything but the liquid. It should be beautifully clear with a pale gold color.
Cover the mixing bowl and let it cool. Now it is ready for use.
Tip: if you don’t have the time to create home-made dashi stock, there’s an instant, powder variety available from Ajinomoto. Buy Ajinomoto’s Hon Dashi stock online or at specialist stores.