until smooth. Batter will be stiff. Spoon into prepared pan and spread batter to fit pan. Arrange apple slices, overlapping, in 2 concentric circles to cover batter. In a small bowl, combine 3 T sugar and cinnamon; sprinkle over apple slices. Dot with 1/2 T margarine. Bake 30 min. Cool 10 min before serving. Cal: 183; Fat: 2 g.