1. In a large bowl, mix together dry ingredients (except coconut). In a separate bowl, mash banana very well and add remaining wet ingredients to it. Add wet to dry and stir until just mixed. Fold in the coconut.
2. Let sit for at least 10 minutes, or it will be too runny! I often put mine in the fridge overnight. The consistency of the batter may change depending on the size of your banana, so add a little flour if it seems too loose or add more milk if it seems too stiff.
3. Pour batter into waffle maker and follow manufacturer's instructions.