Masaharu Morimoto
Makes about 7 cups

Japan’s legendary super-broth is the key to simple home cooking that has deep, satisfying flavor. It requires just fifteen minutes and two ingredients that last virtually forever in your pantry and are easier than ever to find. I can’t think of a better use of your time than making it right away!

4 ounce kombu (dried kelp: an approximately 5 by 6-inch piece)
8 cups water, preferably filtered or spring water
1 ounces bonito flakes (katsuobushi), about 3 cups lightly packed

Briefly and gently wipe the kombu with a damp towel to remove any dirt or grit, but do not scrub off the white stuff.

Combine the water and kombu in a medium pot, set over medium heat, and heat uncovered just until you see small bubbles break the surface of the water, 10 to 12 minutes. Take the pot off the heat.

Use tongs to remove and discard the kombu. Add the bonito flakes to the pot and stir gently to distribute the flakes throughout the liquid. Let the flakes steep for about 1 minute and use a spoon skim off any white froth from the surface of the liquid. Let the flakes steep for 2 minutes more.

Line a sieve or strainer with cheesecloth or sturdy paper towels, set the sieve over a large container, and pour in the dashi. Very gently press the flakes and discard them.

If you’re not using the dashi right away, let it cool to room temperature and store it in an air-tight container in the fridge for up to 4 days, or in the freezer for up to 3 months.