Preheat your waffle maker. Beat egg yolks, buttermilk, milk, cake flour, baking powder, salt, oil, rosemary, and coconut crystals together with an electric mixer. Beat on low until just mixed. Increase speed to high until smooth.
In a small bowl beat egg whites until stiff and fold into the batter.
Cook according to your Belgian waffle maker’s manufacturer’s instructions.
Serve with your favorite spicy maple syrup or use for sammies!