Instructions

1. Add water and kombu to a stockpot and let kombu steep at room temperature for at least 30 minutes (you can soak the kombu for up to 6 hours if you have the time to wait).
2. Place pot over medium heat and bring to a boil.
3. Remove kombu right before water reaches full boil.
4. Turn heat off and allow liquid to cool slightly (you can also add a tablespoon or two of cold water to cool quicker).
5. Add bonito flakes and stir until mixed in. Bring liquid to a boil again.
6. Once boiling, decrease the heat to low and lightly simmer for 5 minutes, skimming off any foam that rises to the top.
7. Turn off heat and let steep for 10-15 minutes.
8. Strain liquid through cheesecloth or a fine sieve to remove bonito flakes from the liquid (straining through a couple paper towels will work in a pinch).
9. Use dashi immediately, or store in the fridge for up to one week. You can also store unused dashi in the freezer for a month or so.