• Preheat oven to 375F. Grease a 9x13-inch pan with non-stick cooking spray; set aside.
• In a medium bowl, whisk together the flour, baking soda, and salt; set aside.
• In large mixing bowl, beat together the granulated sugar and softened butter with an electric mixer until light and fluffy. Add the eggs and beat until well combined.
• Beat in the sour cream, mashed bananas, and vanilla extract.
• Add the dry mixture to the wet and stir just until combined.
• Pour the batter into the prepared baking pan and spread out edge to edge.
• Bake the cake at 375F for 25-30 minutes until a toothpick inserted into the center comes out clean.
• Remove the cake from the oven and cool to room temperature.

Frosting:

• Melt the butter in a skillet over medium heat and continue to cook until the butter begins to turn a light amber brown.
• Remove the pan from the heat and whisk in the powdered sugar and vanilla. The frosting will be thick and chunky.
• Add 2 tablespoons of heavy whipping cream and whisk until the frosting is smooth, adding more cream a tablespoon at a time until the desired consistency is reached. It’s best when smooth and thick enough to spread but can also be made thinner to drizzle over the cake.
• Spread the frosting over the completely cooled cake.