Preheat waffle iron with manufacturer indications.
Preheat oven at 250°F (120°C).
In a bowl, mix dry ingredients.
In another bowl, whip milk with butter, egg yolks and vanilla. Add this preparation to dry ingredients. Whisk until homogenization.
With an electric mixer, whisk egg whites at high speed until it forms firm peaks. Add slowly egg whites to the first mixture by folding with a spatula.
Pour a bit of paste at the center of waffle iron, without filling it too much. Cook for 4 to 6 minutes, depending on manufacturer instructions. When there's no more steam coming out of the waffle iron, try to lift up the lid. If there is resistance, then waffles aren't ready yet. Cook for 1 to 2 minutes more. Gradually, as waffles are cooked, lay over a baking sheet, without stacking it, and set aside in oven. Serve with fruits and maple syrup.
No waffles without waffle iron!
If you want your waffles to look like ones in restaurants, you absolutely need a waffle iron. On market there is for all kind of budget and all shapes. Some "intelligent" model even indicates when to pour the preparation and when to remove it when it's cooked.