Using a standing mixer or a regular hand electric mixer, beat the butter and sugar until light and fluffy.
Incorporate the eggs, and keep mixing.
Add the mashed bananas and mix everything well. Stop the mixer and grab a spatula.
Incorporate the flour and baking powder into the batter, mixing slowly with the spatula.
Add the walnuts and chocolate chips. Do not overmix the batter.
Cover a cookie sheet with parchment paper and drop dollops of batter using a spoon or a medium ice cream scoop, spacing them about 2 inches apart.
Bake at 350F for about 14-15 minutes or until the cookies are golden brown.
Transfer cookies to a wire rack and let them cool completely.
Notes
Storage Tips: These cookies keep well in an airtight container at room temperature for up to 5 days. For longer storage, they can be frozen and enjoyed within 2 months. Just make sure they're completely cool before storing.
Customization Ideas: Feel free to play around with the nuts and chocolate chips in this recipe. Almonds, pecans, or even a mix of your favorite nuts can work beautifully. Dark chocolate chips or white chocolate chips are also delicious alternatives.
Banana Ripeness: The riper the bananas, the sweeter and more moist your cookies will be. Look for bananas that are soft and have lots of brown spots.
Serving Suggestion: These cookies are fantastic on their own, but for an extra special treat, pair them with a cold glass of milk or a cup of coffee. They also make a great ice cream sandwich base.