The night before serving, mix the starter, water, and flour together in a large bowl. Cover and let sit at room temperature overnight or for 8-12 hours.
In the morning, add the baking soda, baking powder, salt, sugar, oil, and egg yolks to the starter mixture. Whisk just until combined. Beat the egg whites in a glass bowl until they hold stiff peaks; fold into the waffle batter.
Heat your waffle iron. When it is hot, brush it with oil, and scoop in some batter. Cook until golden brown.
Serve waffles warm with maple syrup, cream, fresh fruit, or any of your favorite toppings.
Notes
-You may need more or less flour depending on the consistency of your sourdough starter. It's better to have a batter that is too thick, if it is too thin it sticks to the waffle iron.,