For salsa, in a medium bowl combine sweet-and-sour sauce, garlic, cilantro or parsley, lemon juice, and crushed red pepper. Stir in peaches, pear, and the 1 tablespoon chopped onion. Cover and chill up to 4 hours.
In another medium bowl combine the chicken, remaining 1/2 cup onion, basil, seasoned salt, black pepper, and hot pepper sauce; mix well. Shape into four 3/4-inch-thick patties. Grill meat on the grill rack directly over medium-hot coals for 14 to 18 minutes or until an instant-read thermometer inserted in side of patty registers 165 degrees F, turning once. (Or, grill, covered, indirectly with medium heat for 20 to 25 minutes.) Serve burgers with salsa. Makes 4 servings.