Preheat oven to 350°F. Grease 9-inch springform pan with additional butter and flour. Beat egg yolks with 3/4 cup sugar until light in color and double in volume. Stir in whole milk, vanilla extract, flour and baking powder. In another bowl, beat egg whites to soft peaks. Gradually add remaining 1/4 cup sugar and beat until firm but not dry. Fold egg whites into flour mixture. Pour into prepared pan, then place in oven and bake 45 minutes until golden and center is springy. Cool 10 minutes, then loosen edge of cake with knife before removing side of pan. Cool cake completely and place on deep serving plate. Prick cake all over with skewer or two-prong fork. To prepare milk syrup, combine sweetened condensed milk, evaporated milk and whipping cream. Slowly pour milk mixture over cake until it is absorbed. Serve with whipped cream, if desired. If you want to frost cake, cover with plastic wrap and refrigerate at least three hours before frosting.