In a large bowl, mix two and one-quarter cups of Bisquick, one-half teaspoon of baking soda, one teaspoon of cinnamon, and one-half teaspoon of salt.
In another bowl, mix three eggs, one-half cup of milk, three tablespoons of cooled melted butter, and three tablespoons of brown sugar.
Add the three mashed bananas, one-half cup brewed coffee, and two tea spoons vanilla, and mix well. Blend the wet ingredients into the dry with an electric mixer. (Gently stir in a handful of chocolate chips if you wish).
Preheat and grease the waffle iron, and add the batter accordingly.
Cook each waffle until brown.
Serve warm with your choice of whipped cream, sliced bananas, chocolate sauce, or syrup. You could even throw a few chopped walnuts on top. Be creative and enjoy!