PREHEAT oven to 450°F. Toss potatoes with dressing and pepper in greased 15x10x3/4-inch baking pan. Spread into single layer.
BAKE 20 min. Stir in onions. Continue baking 20 min. or until vegetables are tender.
SPRINKLE with parsley and bacon; stir. Top with cheese. Bake an additional 2 min. or until cheese is melted.
serving size = 3/4 cup (175 mL)