1 ¾ cups all-purpose flour, sifted
2 teaspoons baking powder
1 /2 teaspoon baking soda
¼ teaspoon salt
1 lemon, zested
1 ¾ cups of  2 % low-fat milk, at room temperature
¼ cup melted butter
3 eggs, separated, at room temperature
2 tablespoons powdered sugar

 Sift together the flour, baking powder, baking soda and salt in a bowl. 
Stir in the lemon zest. In another bowl, whisk together the milk,
melted butter and the egg yolks until smooth. 
Make a well in the dry ingredients and gradually
stir in the wet ingredients until just combined. 
Do not continue to stir. 
Cover with plastic wrap.
Let stand covered, about 30 minutes. 
Preheat waffle iron according to manufacturer’s instructions. 
In a clean dry bowl whisk the egg whites until fluffy. 
Gradually add the powdered sugar,
while continuing to beat until the whites hold soft peaks. 
Fold gently into batter. 
Ladle batter into prepared waffle iron and cook according to
manufacturers directions.