Food EditionCookJapaneseDinnerMaking Proper Dashi
25 minEasyServes 4 cups
Japanese · Dinner

Making Proper Dashi

You are not looking to cook the ingredients until they fall apart; you are looking to coax their essence into the water. If you boil the kombu, you will get a slimy texture; if you boil the bonito, you will get a fishy, clouded mess.

Total time
25 min
Hands-on
10 min
Serves
4 cups
Difficulty
Easy
Before you start

Watch the temperature, not the clock.

The flavor is held in the delicate oils of the kelp and the smoke of the bonito; high heat destroys both.

  • Medium saucepan
  • Fine-mesh sieve
  • Cheesecloth or coffee filter
Ingredients

What goes in.

  • 4 cupswater, preferably filtered
  • 1 piece (about 4x4 inches)kombu (dried kelp)
  • 1 cupkatsuobushi (shaved dried bonito flakes)
The key technique

Remove before the boil

The kombu must be pulled out the moment the water begins to shimmer with tiny bubbles. If it hits a rolling boil, the liquid will turn bitter and viscous.

Step by step

The method.

  1. Soak the kombu

    Place the water and the piece of kombu in your saucepan. Let it sit for 20 minutes if you have time, though this can be skipped in a pinch.

  2. Heat gently

    Set the pan over medium-low heat. Watch closely for the very first sign of small bubbles forming around the edges of the kelp. Lift the kombu out immediately and set it aside.

  3. Infuse the bonito

    Once the water is at a near-boil, turn off the heat entirely. Add the katsuobushi flakes all at once.

  4. Steep

    Let the flakes sink to the bottom of the pot, which usually takes about 2 to 3 minutes. Do not stir.

  5. Strain

    Line your sieve with cheesecloth or a coffee filter and pour the broth through into a clean bowl. Do not squeeze the flakes, as this forces out bitter particles.

Variations

Other turns to take.

Kombu Dashi

A vegan-friendly version using only the kombu soak. Ideal for delicate vegetable dishes.

Niban Dashi

A second, milder extraction made by boiling the used kombu and bonito flakes in fresh water for 10 minutes. Use this for hearty soups or braises.

Tips & troubleshooting

When it doesn't go to plan.

Tip

Wipe the kombu with a damp cloth to remove grit, but do not wash off the white powdery substance on the surface; that is pure glutamate.

Tip

Store the finished dashi in the refrigerator for up to three days, or freeze it in ice cube trays for easy use later.

Tip

High-quality katsuobushi should be thin, translucent, and curl when they hit the hot water.

Questions

The ones that keep coming up.

Can I reuse the kombu and bonito?

Yes. Keep them in a bag in your freezer and use them together to make a secondary, weaker stock later.

Why is my dashi cloudy?

Usually, this happens because the bonito flakes were boiled or the liquid was agitated too much during straining. Keep the heat off and the movement minimal.

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