Gather your ingredients; mashed bananas, brown sugar, butter, granulated sugar, vanilla extract, egg, old-fashioned oats, salt, and chocolate chips.
Mix banana, brown sugar, butter, sugar, and vanilla into bowl and mix with a mixer on medium speed until smooth.
Once smooth add in egg; beat well.
In a seperate bowl, whisk flour, oats, and salt together.
Add flour mixture to banana mixture and beat with a mixer on medium speed until well blended. Stir in chocolate chips.
Drop batter by spoonfuls two inches apart onto baking sheets coated with cooking spray.
Bake at 350 degrees for 12 minutes. Let cool on pans for 2 minutes.
Take cookies off pan and let cool on a rack.