Combine butter and sugar until light and fluffy. Blend in egg. Add flour; mix well. Spread dough onto bottom of 10" springform pan. Bake at 450 degrees F, 10 minutes.

Combine cream cheese, sugar and flour, mixing at medium speed on electric mixer until well blended. Add eggs, one at a time, mixing well after each addition. Add peaches and liqueur; mix well. Pour over crust. Bake at 450 degrees F, 10 minutes. Reduce oven temp to 250 degrees F and continue baking 65 minutes. Loosen cake from rim of pan; cool before removing rim of pan. Chill. Garnish with additional peach slices and sliced almonds, if desired.