Directions

1. Coat grill rack with nonstick cooking spray. Preheat grill to medium (300°F to 350°F). Brush onion slices and pepper strips with olive oil; set aside. Rub chicken on both sides with mesquite seasoning.
2. Place chicken on grill rack; grill, uncovered, 12 to 15 minutes or until an instant-read thermometer inserted in chicken registers 165°F, turning once halfway through grilling and brushing with barbecue sauce. Top chicken with cheese during the last 2 minutes of grilling.
3. Meanwhile, place onion and bell pepper on heavy foil alongside chicken on grill rack. Grill 10 to 15 minutes or until tender, stirring occasionally.
4. Place chicken on toasted rolls, top with grilled vegetables, and serve.