Place chicken in a shallow dish. Pour salad dressing over chicken; cover and marinate 6 to 8 hours or over night in refrigerator.
Remove chicken from marinade. Place on grill over hot coals 10 minutes on each side or until done.
During the last five minutes that chicken is cooking, toast buns by spraying the inside of the bun with butter flavor cooking spray. Place under the broiler rack and broil on high until buns are golden brown, about 3-5 minutes. Keep a close eye on them or they will burn fast!
Dress buns the way you want them and place chicken on the bun.