Combine first 4 ingredients in a small bowl; stir well. Add milk and margarine, stirring just until flour mixture is moist. Divide batter evenly between 2 (10-ounce) custard cups coated with cooking spray. Top each with 1/2 cup blueberries.
Bake at 375° for 35 minutes or until lightly browned and fruit topping is bubbly.