Here’s a tip, leave the cream cheese and butter for the frosting out while you make the cake, that way they will be softened by the time the cake is cooled and ready to frost. This cake is on the sweet side (it is a cake after all). If you are trying to cut sugars, you may want to experiment dropping the sugar in the cake mixture by a half cup and cutting the amount of frosting in half.
1 Preheat the oven to 350F (175C) . In a medium bowl, whisk together the flour, baking soda, cinnamon, and salt.
2 Beat together in a mixer the butter and sugars. Beat in the eggs one at a time. Mix in the vanilla and mashed bananas.
3 Mix in half of the flour mixture, then the sour cream, then the other half of the flour mixture.
4 Spread batter evenly in a greased 10×15 baking pan. Bake at 350F (175C) for 20 minutes, or until nicely browned and the surface bounces back when you press it with your finger. Cool completely before frosting.
5 To make the frosting, mix all of the ingredients together with an electric mixer. If too stiff to spread, add a teaspoon or two of water. Spread the frosting evenly over the cake and slice to serve.
Yield: Makes 30 pieces.