For waffles: Heat waffle Iron. Separate eggs, putting egg whites in a small mixing bowl and egg yolks in a large mixing bowl. Beat egg whites in a small mixing bowl until soft peaks appear. Set aside. Beat egg yolks, butter (or oil) and milk until frothy. Beat in dry ingredients and vanilla until well blended. Gently fold in egg whites with rubber spatula or wooden spoon. Pour batter using a measuring cup onto center of hot greased waffle iron. Bake until steaming stops, about 5 min. Remove waffle carefully. Repeat with the rest of the batter.