Place ribs in two foil-lined 15x10x1-in. baking pans. Bake at 325° for 2 hours; drain. Cut into serving size portions.
Place ribs in an ungreased 13x9-in. baking dish. Squeeze oranges, reserving 1/2 cup juice and the peel. Combine the juice, barbecue sauce, onion, brown sugar, Worcestershire sauce, chili powder, pepper sauce and cayenne. Cut orange peel into large chunks and add to sauce; pour sauce over ribs.
Bake, uncovered, for 30-45 minutes or until ribs are tender and sauce is thickened, turning ribs several times to coat with sauce. Discard orange peel.