Banana Sheet Cake

Ingredients

• 2 cups all purpose flour
• 1 teaspoon baking soda
• 1 teaspoon cinnamon
• 1/2 teaspoon salt
• 1/2 cup unsalted butter
• 1 cup white granulated sugar
• 1/2 cup brown sugar
• 2 eggs
• The scraped insides of one vanilla bean, or 1 teaspoon of vanilla extract
• 1 cup of mashed ripe bananas
• 1/2 cup full fat sour cream
• 6 ounces cream cheese, room temp
• 4 Tbsp unsalted butter, room temp
• 2 cups powdered sugar
• 1 teaspoon vanilla extract
• 1 teaspoon lemon juice

Directions

1. Heat the oven to 350 degrees F (175 degrees C). In a medium bowl, whisk the flour, baking soda, cinnamon, and salt until they are evenly combined.
2. In a mixer, beat the butter with both sugars until blended. Add the eggs one at a time, beating after each addition, then mix in the vanilla and mashed bananas.
3. Add half of the flour mixture to the batter and mix it in. Blend in the sour cream, then finish with the remaining flour mixture.
4. Spoon the batter into a greased 10x15 baking pan and smooth it into an even layer. Bake at 350 degrees F (175 degrees C) for 20 minutes, until the top is well browned and springs back when gently pressed with your finger. Cool the cake all the way before adding the frosting.
5. For the frosting, beat all of the frosting ingredients together with an electric mixer. If it feels too firm to spread, mix in a teaspoon or two of water. Smooth the frosting over the cooled cake, then slice and serve.