Heat oven to 350°F. Line two baking sheets with parchment.
Mash bananas in a bowl until mostly smooth; set aside.
Cream butter, brown sugar, and granulated sugar until light and fluffy, 2 minutes.
Beat in the beaten egg and vanilla until combined.
Stir in the mashed bananas until evenly incorporated.
Whisk flour, baking powder, baking soda, cinnamon, and salt in a separate bowl.
Add dry ingredients to wet and mix just until no dry streaks remain.
Fold in chocolate chips, if using. Rest batter 5 minutes.
Scoop 1½-tablespoon mounds onto sheets, spacing about 2 inches apart.
Bake 10–12 minutes, until edges set and tops look puffed.
Cool 5 minutes on the pan, then move to a rack to finish cooling.
Notes
For extra lift, chill the scooped dough 20 minutes before baking. Try swapping chips for chopped walnuts or white chocolate. Store airtight at room temperature up to 3 days, or freeze up to 2 months.This recipe is an original creation inspired by classic Fluffy Banana Cookies flavors. All ingredient ratios and instructions are independently developed.