Preheat oven to 350. Mash up the banana and mix with egg, Greek yogurt, vanilla, maple syrup, and coffee. Combine all wet ingredients very well.
Add in flour, baking powder, cinnamon, and coffee grinds to the wet ingredients and mix well again.
Grease a muffin tin / mini square bread tin (I got mine on Amazon) with coconut oil spray and evenly pour batter into the vessels. Bake for 20 minutes. This makes 6 BIG muffins / mini loaves of bread or 12 smaller ones. If you make a loaf, bake for 45 to 55 minutes