Preheat the oven to 350 degrees F.
In a medium-sized mixing bowl, mash the banana smooth until only small chunks remain.
Add in the oats, cinnamon, and vanilla extract and mix well.
Lastly, mix in the chocolate chips. You can add in a small amount of water if the mixture is to dry or add more oats if it is too wet.
Line a cookie sheet with parchment paper. Use a tablespoon to scoop the mixture out and place on the cookie sheet. You can roll them up more or flatten them out. I chose to just drop them on the sheet, hence the odd forms.
Bake in the oven for 12-15 minutes. If you double the recipe you may want to increase the bake time to 15-18 minutes. Remove from the oven and let them cool for a few minutes before eating.