Start with adding your sourdough starter to a bowl & add the brown rice flour. Mix it well (it will be quite dry).
Next, add the buckwheat & white rice flour & baking powder, as well as the egg yolks, milk & coconut sugar. Mix until everything's incorporated.
Last, but not least, add the coconut oil & cinnamon & vanilla sugar / extract & incorporate.
Now, add the pinch of salt to your egg whites and bbeat them until stiff and fold them into your waffle dough. The dough is going to be quite thick, which is perfect for waffles.
Bake the waffles as per instructions on your waffle maker & serve topped with icing sugar, yoghurt, berries and / or apple (or other fruit) puree.