Preheat Your Oven: Set your oven to 350°F (175°C) and grease a 9x13-inch baking dish.
Prepare the Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon. Set this aside.
Mix the Wet Ingredients: In a large mixing bowl, cream the softened butter with granulated sugar and brown sugar until it’s light and fluffy.
Add Eggs and Vanilla: Add the eggs one at a time, beating well after each addition. Stir in the vanilla extract.
Incorporate Bananas and Sour Cream: Mix in the mashed ripe bananas and sour cream until everything is fully combined.
Combine Wet and Dry: Gradually add the dry mixture to the wet ingredients, mixing until just combined. Avoid overmixing.
Pour and Bake: Pour the batter into your prepared baking dish and smooth the top. Bake for about 30-35 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool completely.
Make the Cream Cheese Frosting: In a medium bowl, beat together the softened cream cheese and butter until smooth. Gradually add the powdered sugar and mix until fully incorporated. Stir in the vanilla extract.
Frost the Cake: Spread the cream cheese frosting evenly over the cooled cake. Slice and enjoy!