Banana Waffles with Sour Cream

1 cup flour, unbleached
1½ tsp. sugar
1 tsp. baking powder
¼ tsp. baking soda
¼ tsp. sea salt
1 egg, separated
1 cup sour cream
¼ cup milk
¼ cup butter, melted
1 banana, mashed

Sift together dry ingredients and set aside.

Mix together beaten egg yolk, sour cream, milk, butter and banana.

Add to flour mixture, mixing well.

Fold in egg white which has been whipped until stiff.

Pour into oiled waffle iron and bake until brown.