Beat first 4 ingredients at medium speed with an electric mixer until smooth; stir in cheese, and let stand 10 minutes.
Brush each muffin cup with 1 teaspoon oil, and place in a 450° oven for 10 minutes. Remove from oven and spoon in batter, filling each cup three-quarters full.
Bake at 450° for 25 minutes or until browned and puffy. Serve immediately.