Yield: 7 Cups
2 ounces dried kombu
2 tablespoons dried bonito flake
For the Dashi
Heat circulator water bath to 185 degrees Fahrenheit (85 degrees Celsius).
Place kombu in a clean 2-quart Mason jar with a new lid and band and pour in 1 3/4 quarts (7 cups) cold water. Cover with lid and then tighten band so that it’s finger-tight.
Submerge jar in circulator water bath, with water level a couple of inches below top of jar, and cook for 2 hours. At the 2-hour mark, carefully remove jar lid while it is still in hot water bath and add bonito flakes. Seal jar once again and cook for 15 minutes more. Using a jar lifter or tongs and some dexterity, carefully remove jar from water bath. Strain dashi into a clean container. Use it immediately, or let it cool in the refrigerator where it will keep for a couple of days. Or transfer dashi to 1-cup containers and freeze them for up to 6 months.
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