In the bowl of an electric stand mixer fitted with the paddle attachment beat the margarine with the brown sugar and sugar until light and fluffy.
Add the peanut butter and banana and beat until smooth.
Add in the egg and beat until smooth.
Add in the flour, baking soda, salt, and vanilla and mix on low until the dough forms.
Add in the chocolate chips and mix until chips are incorporated.
Scoop cookies onto parchment lined cookie sheet using a medium sized cookie scoop. Press the top of each cookie in two directions with a fork to slightly flatten.
Bake for 8-10 minutes until the edges are slightly golden brown.
Cool on wire rack and enjoy!
Recipe by Lil' Miss Cakes at https://lilmisscakes.com/2014/peanut-butter-banana-chocolate-chip-cookies