Mash the bananas in a mixing bowl. Add the eggs and coconut milk and whisk well until combined. Add the coconut flour (and cinnamon, vanilla extract if adding) and mix well. The batter will be thick. Allow batter to sit for at least 15 minutes (you can refrigerate it for up to 1 day ahead of time).
Heat up your waffle iron and lightly spray it with cooking oil. Transfer the waffle batter to the waffle iron. If adding chocolate chips, sprinkle on top of batter before replacing the lid. Cook until golden-brown, crispy and cooked through.