Spicy, Tart Dipping Sauce for Seafood

Directions

1. Cook the chiles, turning them over once or twice, until both sides are completely blistered and almost completely blackened and the flesh is completely cooked, 8 to 10 minutes, depending on the size of the chiles. Remove the chiles from the skewers and use your fingers or a small knife to peel them. You don’t have to remove every last bit of skin. In fact, you want to see bits of char in the finished sauce.
2. Combine the cilantro roots and salt in a granite mortar and pound to a fairly smooth, slightly fibrous paste, about 30 seconds. Pound in the garlic until it’s fully incorporated, about 1 to 2 minutes. Add the chiles and pound them until you have a fairly smooth paste (the seeds will still be visible), about 1 minute more. Scrape the paste into a bowl or other container, then add the lime juice, fish sauce, and sugar, and stir well.
3. Let the sauce sit for an hour or two before you serve it. It’ll taste even better after it does. Right before you serve it, stir in the cilantro.