Place turkey slices in shallow dish or resealable plastic bag. In small bowl, combine barbecue sauce, bell pepper and onion; mix well. Pour over turkey slices; turn to coat well. Cover dish or seal bag; let stand at room temperature for 15 minutes to marinate.
Line 15x10x1-inch baking pan with foil; spray foil with nonstick cooking spray. Place turkey slices in sprayed foil-lined pan; reserve marinade.
Broil 4 to 6 inches from heat for 4 minutes. Turn slices; baste with remaining marinade. Broil an additional 2 to 4 minutes or until turkey is no longer pink.