Grilled Steak Tacos with Pickled Peach and Onion

Name: Grilled Steak Tacos with Pickled Peach and Onion
Ingredients: ONION COMPOTE:; 1 teaspoon olive oil; 2 onions, chopped; 2 teaspoon light brown sugar; 1/3 cup red wine; 1 tablespoon red wine vinegar; STEAK BURGERS:; 1/4 cup oil-packed sun-dried tomatoes, well drained; 1 pound skirt steak, trimmed of visible fat, cut into chunks; 1 tablespoon chili powder; 1/2 teaspoon salt; 1/4 teaspoon freshly ground black pepper; 4 whole wheat kaiser rolls (2 ounces each), toasted; 4 slices tomato; 4 leaves green-leaf lettuce