Preheat your oven to 350°F (175°C). Grease and flour your 9x13-inch baking pan.
In a mixing bowl, mash the ripe bananas until smooth.
In another bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
Add the eggs and vanilla extract to the butter mixture, beating well to combine.
Mix in the mashed bananas.
In a separate bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon (if using).
Gradually add the dry ingredients to the wet mixture, mixing until just combined. Be careful not to over-mix.
Pour the batter into the prepared baking pan and smooth the top with a spatula.
Bake in the preheated oven for about 45 minutes, or until a toothpick inserted in the center comes out clean.
Remove the cake from the oven and let it cool in the pan for about 10 minutes before transferring it to a cooling rack to cool completely.
While the cake is cooling, prepare the cream cheese frosting. In a mixing bowl, beat the softened cream cheese and butter until smooth and creamy.
Gradually add the powdered sugar, mixing until well combined. Stir in the vanilla extract. If the frosting is too thick, add milk a tablespoon at a time until you reach your desired consistency.
Once the cake is completely cool, spread the cream cheese frosting evenly over the top of the cake.
Slice and serve!