Add oats to a high speed blender and blitz till a flour like consistency. Add in the banana + milk + baking powder. Blitz till smooth.
Leave the batter to rest while you heat up a waffle iron till hot, brush with coconut oil and pour in the mix. You may have a lil bit of mix left over for 1 more waffle.
Cook for 10 mins or until crisp and pulls away from edges easily.