Ponzu Sauce

This tart and refreshing sauce can be used for dipping pieces of raw fish or for spooning over hot seafood. Using ponzu sauce is much like using lemon juice, except for the smokiness of the bonito flakes and the sweet-and-sour flavor provided by the vinegar and mirin. For a decorative touch, use the julienned lime zest.
This sauce is made a day ahead.

MAKES ABOUT 1 CUP

• 5 limes
• ⅓ cup fresh lemon juice (from about 5 lemons)
• 3 tablespoons rice vinegar or sherry vinegar
• ⅓ cup dark Japanese soy sauce
• 2 tablespoons mirin
• 1 cup bonito flakes

Trim away the zest from 1 lime and reserve.
Squeeze the juice from all 5 limes and put the juice into a saucepan with the lemon juice, vinegar, soy,
mirin, and bonito flakes. Cover and let stand at room temperature for 24 hours.

Strain through a fine-mesh strainer into a bowl.
Cut the lime zest into fine julienne, blanch in boiling water for 1 minute, and drain. Add the zest to the
sauce. The sauce can be tightly covered and refrigerated for about 2 weeks or frozen for up to a few months.