To begin, preheat your oven to 350 and line two pans with parchment paper.
In a small mixing bowl, add your dry ingredients and stir them together (flour, baking soda, cinnamon and salt).
In a large mixing bowl, add your coconut oil and brown sugar and cream them together with a hand mixer for a minute, or till well combined. Add your mashed banana and blend together again. Add your vanilla and egg and blend together one more time.
Pour your dry ingredients into your wet ingredients and stir them together till you have a smooth cookie dough batter. Add your oats and chocolate chips and gently fold them into the batter.
*For thicker cookies, chill your cookie dough batter in the fridge for 15-30 minutes.*
Using a small cookie scoop, scoop your dough evenly spaced apart onto your pans, with twelve cookies on each pan. Bake in the oven for 11-14 minutes, or till the edges are set and just starting to gain some color.
Let mostly cool on the pan, and then remove to a cooling rack till all cookies are entirely cool.
Devour!
You can store these cookies in an airtight container on the counter for 2 days, or up to a week in the fridge.