Stir dry ingredients into mixing bowl. Make well in center. Add slightly cooled melted margarine to beaten eggs, milk and vanilla. Add all of liquid mixture to dry mixture, stirring quickly - only 15 to 20 seconds. Batter will seem lumpy. Immediately pour into greased muffin tin, 2/3 full, and bake at 400 degrees for 15 to 20 minutes. Remove at once. May sprinkle cinnamon over batter or stir into batter.