PREHEAT barbecue to medium-high heat. Cook and stir onions and peppers in oil in skillet on medium heat until tender; set aside.
GRILL chicken 8 min.; turn over. Brush with barbecue sauce. Grill an additional 7 to 9 min. or until chicken is cooked through (170°F), turning occasionally and brushing with the remaining barbecue sauce. Top chicken with Singles. Grill an additional min. or until Singles are melted.
FILL rolls with chicken, onions and peppers.
serving size = 1 sandwich
