Prepare a charcoal or gas grill for high heat (450° to 550°; you can hold your hand 5 in. above cooking grate only 2 to 4 seconds). Rub chicken with olive oil, a splash of vinegar, and salt and pepper to taste.
Grill chicken, turning often, until no longer pink in center. Set on plates and spoon salsa on top.
Servings 0