Preheat oven to 350. Prepare a 12" pizza pan with cooking spray and flour; set aside. To prepare crust, combine margarine, egg white, milk, and vanilla in a mixing bowl. In another mixing bowl, combine flour, granulated sugar, and baking powder. Mix wet ingredients with dry ingredients just until moistened. On a lighty, floured surface, roll dough into a 12" circle. Press into prepared pizza pan. Bake for 7 minutes or until golden brown. Cool. Meanwhile, to prepare topping, combine powdered sugar and cream cheese. Spread over cooled cookie crust to within 1/2" of edge. Spoon cherry pie filling over cream cheese layer. ----