Whisk together the flour, sugar, and baking powder in a large bowl.
Stir together the egg yolks, milk, butter, and vanilla in a large measuring cup.
Whisk into the dry ingredients until combined, one or two minutes.
In a clean mixing bowl, whip the egg whites until stiff peaks form.
Fold gently into your batter until incorporated.
Heat a waffle iron and lightly mist with cooking spray.
Spoon 3/4 cup batter onto the heated surface.
Cook until crisp.
Top with butter and syrup and enjoy.
Notes
Find a good waffle iron. You want one that has nice deep pockets. In the somewhat altered words of the big bad wolf; All the better to soak up buttery syrup goodness, my dear! I like this one. It gets the job done perfectly and the price is right.
I prefer to hand mix my waffles. This helps keep the inside nice and soft.
Don’t skip whipping the egg whites! Whipping the whites is what gives you that crisp outside.