Preheat oven to 350° and right before filling, spray (2) 8 inch cake pans with non stick spray.
In a large bowl, beat butter and sugar together until creamy.
Add eggs and beat until combined then beat in sour cream and vanilla.
Next, add flour, baking soda and salt then beat just until combined.
Stir in mashed bananas and mix until combined.
Pour equally into prepared cake pans and bake for approximately 35-40 minutes or until toothpick inserted comes out clean.
In a medium bowl, beat cream cheese and butter together until combined then add vanilla.
Gradually add powdered sugar and beat until smooth and creamy.
Once cake has cooled, frost cake and enjoy!