Dashi Stock

Instructions

1. Prepare the kombu
   Gently wipe the kombu with a damp cloth to remove any impurities, but do not wash it as this would remove the flavorful white powder on its surface. Using scissors, make a few small cuts along the edges of the kombu to help release more flavor.
2. Cold infuse the kombu
   Place the kombu in a large pot with the cold water. Let it soak for at least 30 minutes (or up to 3 hours in the refrigerator for a deeper flavor). This extracts the umami compounds from the seaweed.
3. Heat the kombu water
   Place the pot with kombu and water over medium-low heat. Heat slowly until small bubbles begin to form around the edges of the pot, just before it reaches a simmer (around 160°F/70°C). This should take about 10 minutes. Do not let it boil as this will make the dashi bitter.
4. Remove kombu and add katsuobushi
   Just before the water boils, remove the kombu from the pot. Add the katsuobushi flakes and any optional ingredients (dried shiitake, niboshi, sake) if using. Bring to a gentle boil, then immediately reduce heat and simmer for just 30 seconds.
5. Let the flavors infuse
   Turn off the heat and let the katsuobushi sink to the bottom of the pot, about 5 minutes. The longer you let it sit, the stronger the flavor will be, but don't exceed 10 minutes or it may become bitter.
6. Strain the dashi
   Line a fine-mesh strainer with cheesecloth or a paper towel and place it over a large bowl or another pot. Gently pour the dashi through the strainer to collect the clear broth. Do not press on the solids as this can make the broth cloudy and bitter.
7. Season and store
   If using, add sea salt and white soy sauce to taste. The dashi is now ready to use. It can be stored in an airtight container in the refrigerator for up to 4 days, or frozen in ice cube trays for future use.