Pre-heat and coat the waffle iron grids with cooking spray
Sift the flour, baking powder, baking soda, and salt onto a square of wax/parchment paper (or mix in bowl). Set aside
In a medium bowl, beat the egg whites with an electric mixer until stiff. Set aside
In a large bowl, beat the egg yolks with a fork. Whisk in the buttermilk and oil. Add the flour mixture and stir just unti the large lumps disappear. Fold in the egg whites
Pour about 1 cup batter (whatever waffle iron holds) evenly onto pre-heated grid. Close the lid and bake until crisp and golden brown.
Serve with butter and syrup, or other toppings as desired.
Note: if you do not have buttermilk, make sour milk by measuring 2 tablespoons of lemon juice or vinegar into a 4-cup glass measuring cup. Add regular milk to make 2 1/4 cups. Stir. Let stand for five minutes.
Variations:
Basic Waffles: Substitute regular milk for the buttermilk, increase the baking powder to 1 tablespoon, and omit the baking soda