Mix the flours, baking powder, baking soda, and salt in a medium bowl.

In another bowl mix together the egg yolks, Kefir, butter or coconut oil, sugar and vanilla until smooth.

In the bowl of a stand mixer or with a hand mixer beat the egg whites until stiff peaks form. You want them to just stand up on the end of the whisk when finished.

Add the flour mixture to the egg yolk mixture until incorporated but do not over mix.

Slowly fold the egg whites into the flour mixture. You don't want all of the air to come out. So just use a folding technique to fold the batter over the egg whites until it's all mixed together.

Heat up your waffle iron and get to it. My waffle iron has settings from soft to crispy. I set mine just past the medium setting. This gives me a fluffy inside and crunchy outside.