To Die For Banana Cake with Vanilla Bean Frosting

from ButterYum
makes one 8x8-inch pan (double recipe for a 9x13-inch pan)



  • 2/3 cup sugar 
  • 1/2 cup sour cream
  • 1 egg
  • 2 tablespoons unsalted butter, softened
  • 3/4 cup mashed super ripe banana (about 2)
  • 1 teaspoon pure vanilla extract 
  • 1 cup flour
  • 1/4 teaspoon salt
  • 1/2 teaspoon baking soda


  • 2 tablespoons unsalted butter, softened
  • 1 1/4 cups confectioner's sugar, sifted
  • 1/4 cup heavy cream
  • 1/2 teaspoon vanilla bean paste* (see below)


To make cake (is easily mixed by hand):

  1. Preheat the oven to 375F (see note below). 
  2. Cream together sugar, sour cream, egg, and 2 tablespoons softened butter. 
  3. Add mashed bananas and 1 teaspoon vanilla extract. 
  4. Add flour, salt, and baking soda; mix well. 
  5. Pour into greased 8x8-inch pan. 
  6. Bake at 375F for 20-25 minutes until a toothpick inserted in the center comes out clean. 
  7. Cool completely before frosting.

To make frosting:

  1. Cream butter and confectioner's sugar together until smooth. 
  2. Slowly add the heavy cream and vanilla bean paste; stir until smooth.  
  3. Spread on cooled cake. 


  • Vanilla bean paste is a product that can be purchased at gourmet groceries or you can order it online (linked below).  Here's the general rule for substituting vanilla: 1 vanilla bean = 1 tablespoon vanilla powder = 1 tablespoon vanilla bean paste = 1 tablespoon pure vanilla extract.
  • Bake at 350F if using a glass pan.