Preheat the oven to 350 degrees. Use convection bake if you have it.
Use a hand or a stand mixer to cream together the softened butter and cream cheese. Make sure that both ingredients are at room temperature before mixing them.
Add the granulated sugar and mix until smooth. Scrape down the bowl once complete.
Add the room temperature eggs and vanilla extract. Mix until combined.
In a separate bowl, whisk together the dry ingredients (flour, salt and baking powder).
Add the dry ingredients to the wet ingredients in 2-3 portions, mixing well after each addition. Scrape down the bowl once complete.
Line 1-2 large cookie sheets with parchment paper (or spray well with baking spray).
Use a large cookie scoop (or just your hands) to form 3-inch cookie dough balls. Press them down lightly on the cookie sheet before baking. Leave at least 2 inches between each cookie.
Bake the cookies for 18-24 minutes or until the bottoms and tops of the cookies just begin to brown.
As soon as you remove the cookies from the oven, use a large cookie dough scoop or a 1/4 measuring cup to make indents on the cookies. Set them aside to allow them to cool to room temperature while you make the banana cream filling.