Bonito flakes

Bonito flakes, katsuobushi in Japanese, are thin shavings of skipjack tuna that has been simmered, smoked and dried until it is as hard as wood. They are pale pink-brown, light as paper and smell smoky and savory. Together with kombu, they are the base of dashi, the stock behind miso soup, noodle broths and many Japanese sauces.

How to use it

To make a basic dashi for about 1 liter (4 cups):

1. Soak 10 g of kombu in 1 liter of cold water for 30 minutes.
2. Heat slowly and take the kombu out just before the water boils.
3. Bring to a boil, turn off the heat and add 20 g (about 2 loosely packed cups) of bonito flakes.
4. Let the flakes sink for 2 to 3 minutes, then strain through a fine sieve lined with a paper towel or cloth. Do not squeeze the flakes, or the stock turns cloudy and fishy.

You can also use the flakes as a topping. Scattered on hot food such as okonomiyaki, takoyaki or blanched spinach, they curl and move in the steam, which is why people say they "dance". Mixed with soy sauce, they make a quick seasoning for rice.

Substitutes

• Instant dashi granules, dissolved following the pack.
• For a fish-free stock, use kombu with dried shiitake mushrooms. It is milder and earthier but still rich in umami.
• For a topping, toasted nori strips or toasted sesame seeds fill the space, but not the smoky taste.

How to store it

Keep the bag tightly closed with the air pressed out, in a cool, dark place. Moisture makes the flakes soft and lets them go stale. Once opened, use them within a few weeks, or keep the bag in the fridge or freezer to hold the aroma longer.

Common mistakes

• Boiling the flakes in the stock. Long or hard boiling makes dashi bitter and fishy.
• Buying large, thick shavings for a topping. These are made for stock. Use thin, fine flakes for sprinkling.

Bonito is a fish, so anyone with a fish allergy should avoid it and dishes made with dashi.