In a small bowl combine flour, baking powder, baking soda, and salt. Stir with a wooden spoon to combine. Set aside.

In a large bowl add sugar, brown sugar, and butter. Beat with a mixer until fully incorporated and smooth. Add egg, egg yolk, mashed banana, vanilla extract, and peanut butter. Beat mixture again until smooth and all ingredients are fully combined.

Add dry mix into the wet mixture and stir with a wooden spoon until batter is smooth.

Add in chocolate chips and stir until combined.

Cover and refrigerate cookie dough for 30 minutes.

Preheat oven to 350°F

Scoop out about ¼ cup of cookie batter and roll into a ball using your hands. Place cookies on baking sheets, leaving lots of room between the cookie dough balls, keeping in mind they will spread out as they bake. I usually only place 6 cookie dough balls on one baking sheet.

Bake for 16-18 minutes until cookies are golden brown. Remove cookies from the oven and transfer to a cooling rack. Let the cookies cool completely before serving.