Cream margarine, M-K Butter Flavor and sugar in mixer about 3 minutes. Add egg yolks, one at a time, beating well after each addition. Stir in M-K Pure Vanilla Extract. Sift flour twice. Add baking soda and M-K Ground Nutmeg and sift again. Add sour cream alternately with the flour. Beat egg whites until stiff, but not dry. Gently fold into cake batter. Bake this in two bread pans, greased and lined with waxed paper or you may use a heavy tube pan. Bake 1 hour s and 15 minute at 300°. Allow cake 5 to 10 minutes to cool before removing from pans. This cake freezes well and does not need icing.