PREHEAT oven to 350°F. Combine dressing, broccoli, peppers, Parmesan cheese and 1/2 cup of the mozzarella cheese.
SPREAD into 1-L baking dish or 9-inch pie plate.
BAKE 20 to 25 min. or until heated through. Sprinkle with remaining 1/2 cup mozzarella cheese. Bake an additional 5 min. or until mozzarella cheese is melted.