1Heat oven to 400°F. Spray 9-inch square pan with cooking spray. In medium bowl, stir Bisquick mix, 2 tablespoons sugar, the milk, 2 tablespoons butter and egg until well blended. Spread batter evenly in pan.
2Arrange apple slices in 3 rows, overlapping slices slightly, on batter. Brush 1/4 cup melted butter over tops of apple slices.
3In small bowl, mix 2 tablespoons sugar and the cinnamon; sprinkle over apples.
4Bake 16 to 18 minutes or until edges are golden brown. Cool 15 minutes before serving. Cut with serrated knife into squares.