HEAT oven to 400ºF.
COOK chicken and vegetables in large skillet sprayed with cooking spray on medium-high heat 4 to 5 min. or until chicken is no longer pink, stirring occasionally.
PLACE crust on baking sheet; spread with barbecue sauce. Top with chicken mixture and cheese.
BAKE 15 to 18 min. or until cheese is melted and crust is golden brown.