Brush both sides of eggplant slices with oil. Place on an ungreased baking sheet. Bake at 400° for 8 minutes. Turn and bake 7-8 minutes longer or until lightly browned and tender. Cool on a wire rack.
Place one eggplant slice in each of two 10-oz. ramekins coated with cooking spray. Top each with 2 tablespoons spaghetti sauce and 2 tablespoons mozzarella cheese. Repeat layers twice. Sprinkle with Parmesan cheese. Bake, uncovered, at 350° for 20-25 minutes or until bubbly and cheese is melted.