Preheat waffle iron. And just before adding waffle batter, brush hot waffle iron with melted butter.
Sift together flour, unsweetened cocoa powder, baking powder, brown sugar and salt. Set side.
Pour buttermilk into a bowl, add egg yolks, and vanilla then whisk well.
In the bowl of a stand mixer add egg whites and beat until you get stiff peaks. Set aside.
Melt butter and set aside.
Gently stir buttermilk, egg and vanilla mixture into the sifted flour mixture. Note: emphasis on gently, because over-mixed ingredients produce tough waffles.
Very gently add melted butter until just combined, butter should be warm, NOT HOT.
Now it's time to fold (not stir) in those wonderful egg whites; this is your most secret weapon and how you'll get stupid fluffy waffles. Trust. And it is okay if you see wisps of egg whites, don't panic they will be cook up just fine.
Spoon batter into waffle iron and add a few chocolate chips!
Cook just shy of five minutes.
Remove waffles and brush more butter.
Top with chocolate syrup, bananas, maple syrup or fresh fruit.
