Preheat oven to 325°F.

Grease a 9x13 inch baking pan and set aside.

In a medium bowl, mash the ripe bananas until mostly smooth.

In a separate large bowl, cream together the softened butter and sugar until light and fluffy.

Add the eggs one at a time, mixing well after each addition.

Stir in the vanilla extract and sour cream.

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

Gradually stir the dry ingredients into the wet mixture until just combined.

Fold in the mashed bananas until the batter is smooth.

Pour the batter evenly into the prepared pan and smooth the top.

Bake for 35 to 40 minutes or until a toothpick inserted into the center comes out clean.

Let the cake cool completely in the pan before frosting.

In a mixing bowl, beat the cream cheese and butter together until smooth and creamy.

Add the maple syrup and vanilla extract and mix until combined.

Gradually add the powdered sugar, beating until the frosting is thick and smooth.

Spread the frosting evenly over the cooled banana cake.

Refrigerate for 15 minutes before slicing for cleaner cuts, if desired.

Store any leftovers covered in the refrigerator.