Preheat the oven to 350°F (175°C).

In a mixing bowl, cream together the softened butter and brown sugar until light and fluffy.

Add the mashed bananas, egg, and vanilla extract; mix until well combined.

In another bowl, whisk together the flour, baking soda, baking powder, and salt.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Fold in chocolate chips if using.

Using a cookie scoop, drop dough onto a baking sheet lined with parchment paper, spacing them about 2 inches apart.

Bake in the preheated oven for 10-12 minutes or until the edges are lightly golden.

Remove from the oven and let cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.