HEAT oven to 400ºF.
TOSS potatoes with dressing in 13x9-inch nonstick pan; sprinkle with 1/2 tsp. chili powder. Bake 25 min.
STIR potatoes; push to sides of pan. Place chicken in single layer in center of pan; sprinkle with remaining chili powder. Drizzle with barbecue sauce.
BAKE 20 min. or until chicken is done (165ºF) and potatoes are tender. Transfer chicken to platter. Stir potatoes to evenly coat with pan drippings. Spoon around chicken on platter; top with Parmesan.