Whisk the egg whites until they are firm and form stiff peaks. You have to use a clean, non-greasy bowl for this and be a bit patient.
In a second bowl, mix the egg yolks, coconut flour, sweetener and baking powder.
Add the melted butter slowly and mix well to ensure your batter is nice and smooth.
Add the milk and vanilla, mix well.
Gently fold spoons of the whisked egg whites into the yolk mixture. Try to keep as much of the air and fluffiness as possible.
Place enough of the waffle mixture into the warm waffle maker to make one waffle. Cook until golden. You might have to "grease" your waffle maker with a bit of butter so the waffles do not stick. They have a more delicate consistency than wheat waffles, so take extra care when removing them.
Repeat until all the mixture has been used.
Enjoy with cream and berries or with sugar free syrup!