Roasted Red Pepper and Olive Salsa

Name: Roasted Red Pepper and Olive Salsa
Ingredients: 1/2 cup red or white pearl onions, blanched and peeled; 1 tablespoon unsalted butter; 1 jarred roasted red pepper, finely chopped; 1/2 cup pitted Kalamata olives, thinly sliced; 1/2 cup pitted green Cerignola olives, thinly sliced lengthwise (see the Guide); 1 garlic clove, minced; 2 tablespoons finely chopped fresh flat-leaf parsley; 3 dried red chiles, crumbled; 1/4 cup extra-virgin olive oil; 1/4 cup sherry vinegar; 1/2 teaspoon coarse salt; 1/4 teaspoon freshly ground pepper