1/3 cup fresh lime juice 1 teaspoon sugar 3/4 teaspoon kosher salt 1/4 teaspoon freshly ground black pepper 3 tablespoons olive oil 1/2 cup thinly vertically sliced red onion 1/2 cup coarsely chopped fresh cilantro 1 (16-ounce) package cabbage-and-carrot coleslaw 4 jalapeño peppers, halved crosswise
Combine first 4 ingredients in a large bowl, stirring with a whisk. Gradually add olive oil, stirring constantly with a whisk. Add onion, cilantro, and coleslaw. Thinly slice 1 jalapeño half crosswise (keeping seeds), and remove seeds from remaining jalapeño halves. Cut the remaining halves into thin crosswise slices. Add the jalapeños to onion mixture, and toss well to coat. Cover and chill at least 1 hour.