Ingredients

The following ingredients have 24 Servings
  • 2 cups all purpose flour
  • 2 cups granulated sugar
  • 1 tsp baking soda
  • 1 tsp salt
  • 1/2 cup unsalted butter
  • 1 cup water
  • 1/2 cup creamy peanut butter Note: I used regular peanut butter for this recipe, 'natural'peanut butter does not work as well.
  • 1/2 cup vegetable oil
  • 2 large eggs (room temperature)
  • 1/2 cup buttermilk (room temperature)
  • 1 tsp vanilla extract
  • 1/2 cup unsalted butter
  • 1/2 cup creamy peanut butter
  • 6 Tbsp buttermilk, you might need a touch more if your frosting is too stiff
  • 1 tsp vanilla extract
  • 3 cups confectioner's sugar (sifted)
  • 1/2 cup roasted peanuts

Instruction

  • Preheat oven to 350F and spray a 9x13 pan with nonstick spray.
  • Whisk together the flour, sugar, baking soda, and salt in a medium bowl and set aside.
  • Heat the butter and water in a medium/large saucepan until it comes to a boil. Take off the heat and whisk in the peanut butter and oil until smooth. Let cool for a few minutes, then whisk in the eggs, buttermilk, and vanilla until well blended.
  • Add the dry ingredients to the wet ingredients, and whisk until just combined.
  • Pour the batter into the prepared pan and bake for 40-45 minutes, until the top is golden and a toothpick inserted in the center comes out clean. Set the cake on a cooling rack while you make the frosting.
  • To make the frosting, put the butter, peanut butter, and buttermilk in a saucepan and bring to a full boil. Take off the heat and beat in the vanilla and powdered sugar, adding a cup at a time, until the frosting is smooth. I like to put it back on a gentle heat just to rewarm it, stirring constantly, before pouring over the cake. Note: if your frosting is very stiff and not pourable, add a little bit more buttermilk to thin it out.
  • Pour the hot frosting over the warm cake, working quickly because the frosting sets up immediately. Spread evenly over cake.
  • Garnish with peanuts.