In a large bowl whisk together flour & baking powder.
In a separate bowl, add butter, milk & egg yolks, stirring to combine.
Pour the milk mixture into the flour mixture and stir with rubber spatula until just combined.
Add the beaten egg whites and gently fold to combine.
Heat an 8 inch NONSTICK skillet over LOW heat. Pour 1½ cups of pancake batter into the skillet, smooth out the top, then cover with a lid. Cook until golden brown on the bottom and a toothpick inserted into the center comes out clean, about 20 minutes.
Transfer the pancake to a plate and repeat, making 3 more pancakes with the remaining balter.
Serve with maple syrup and butter.