Banana Sour Cream Waffles

1 cup flour
1/2 tablespoon sugar
1 teaspoon baking powder
1/4 teaspoon baking soda
1/4 teaspoon salt
1 egg, separated
1 cup sour cream
1/4 cup milk
1/4 cup butter, melted
1 banana, mashed

Sift together dry ingredients. Set aside. Mix together beaten egg yolk, sour cream, milk, butter and banana. Add to flour mixture, mixing well. Fold in whipped egg white, and pour into oiled waffle iron or oiled pan. Cook each side until brown.