Dashi Stock

• 8 cups prepared kelp stock
• 4 cups (2 ounces) katsuobushi (dried skipjack tuna flakes)

1. Place the prepared kelp stock in a large pot over medium heat and heat up to 175u0b0 F. At this temperature you will begin to see little tiny bubbles building up and covering the side of the pot. Do not bring the stock to a boil. Add the fish flakes all at once, gently pushing the flakes down into the stock with a spatula. Wait for the stock to come to a gentle simmer, and then quickly turn off the heat. Leave the fish flakes in the stock for about 5 minutes.
2. Strain the stock through a moist paper towel-lined strainer, ensuring that none of the fish flakes pass into your stock, and reserve the fish flakes. Dashi should be very clean and clear; it will be much more flavorful than kelp stock. For best results, use it within three days, or store it in the freezer for later use.
3. After making your first dashi stock, be sure to make a second stock. Combine 6 cups kelp stock and the leftover katsuoboshi. Bring to a gentle boil, lower the heat to medium-low, and cook for 10 minutes. Add 1 cup of tightly packed katsuobushi and turn off the heat, then let sit for 5 minutes. Strain through a moist paper towel-lined strainer.

kelp stock

Taken from food52.com/recipes/21356-dashi-stock (may not work)