Mix cheeses and mayo; spoon into baking dish. Cover. Refrigerate until ready to bake. Bake 15 to 20 min. or until heated through, stirring after 10 min.
Substitute 1 large tomato, seeded and chopped, for the sun-dried tomatoes.
Mix cream cheese, mozzarella cheese, mayo and garlic until well blended. Spoon into 9-inch microwaveable pie plate or casserole dish. Microwave on HIGH 3 min.; stir. Arrange tomatoes, artichokes and peppers over cheese mixture in three separate sections. Microwave on HIGH an additional 2 min.