PREHEAT oven to 400°F.
Mix potatoes and 1/2 cup of the cheese; spoon into 13×9-inch baking dish sprayed with cooking spray.
Top with layers of meat, 1/2 cup of each of the vegetables and the sauce. Cover with foil.
BAKE 40 min. Remove foil; sprinkle casserole with remaining 1/2 cup cheese. Bake an additional 5 min. or until cheese is melted.