Preheat the oven to 350°F. Line two baking sheets with parchment paper.
In a medium bowl, whisk together the flour, baking powder and salt.
In the bowl of a stand mixer fitted with the paddle attachment, cream together the butter, white sugar and brown sugar until light and fluffy, about 2 minutes, scraping down the sides as needed.
Add the eggs one at a time, beating between each addition.
Add the vanilla extract and mashed bananas and mix until combined.
Add the flour mixture and mix just until combined.
Stir in the chocolate chips then scoop the dough onto the prepared baking sheets. Sprinkle them with sea salt (optional).
Bake the cookies for 12 to 15 minutes or until the edges begin to lightly brown.
Remove the cookies from the oven and let them sit on the hot baking sheets for 5 minutes before transferring them to a rack to cool completely.