In small pan, combine brown sugar & 1/2 stick butter; melt, stirring to combine. Spread on bottom of cake pan (9" round)**. Arrange peaches over brown sugar in concentric circles. In small bowl, combine flour, baking powder & cinnamon. In large bowl, beat remaining 1 1/2 sticks butter with sugar until creamy. Beat in yolks. Alternately beat in flour mixture with milk & vanilla until well blended. In small bowl, beat whites to stiff peaks. Fold whites into batter. Spread over peach slices. Bake 55-60 mintues at 350 or until cake tests done. Cool on rack 10 minutes. Turn cake onto plate.

**Can also be made in 9" springform pan or 8X8" square pan.