Sift together flours and sugar, then beat in eggs, milk, salt and vanilla until batter is smooth.

Let batter rest in refrigerator overnight, or at least 30 minutes.

When ready to cook, heat a crepe pan or flat frying pan over medium.

Whisk melted and cooled butter into crepe batter. When pan is hot, pour about 1/4 cup of batter into the center of the pan. Tilt pan to evenly coat it with batter, or use a rateau to spread.

Cook crepe until edges are crispy and the top no longer looks wet (about 2 minutes). If your crepe is thin enough, you will not need to flip. If needed, flip and cook for another minute or so. Fold crepe and set aside until the whole batch is done.