Ingredients

  • Cake:
  • 2 cups all-purpose flour
  • 2 cups white sugar
  • 1 teaspoon baking soda
  • 1/2 cup milk
  • 2 eggs
  • 1 teaspoon vanilla extract
  • 1 cup water
  • 1/2 cup butter
  • 1/2 cup vegetable oil
  • 1/2 cup peanut butter
  • Icing:
  • 1/2 cup butter
  • 1/2 cup peanut butter
  • 1/3 cup milk
  • 1 teaspoon vanilla extract
  • 4 3/4 cups confectioners' sugar

Method

  • Preheat oven to 350 degrees F (175 degrees C). Grease a baking sheet.
  • Whisk flour, white sugar, and baking soda together in a bowl. Beat 1/2 cup milk, eggs, and 1 teaspoon vanilla extract into flour mixture using an electric mixer on low until smooth.
  • Cook and stir water, 1/2 cup butter, vegetable oil, and 1/2 cup peanut butter together in a saucepan over medium heat until smooth, about 5 minutes. Stir peanut butter mixture into flour mixture until batter is well mixed; pour onto the prepared baking sheet.
  • Bake in the preheated oven until a toothpick inserted in the center of the cake comes out clean, about 20 minutes.
  • Melt 1/2 cup butter and 1/2 cup peanut butter together in a saucepan over medium heat until smooth; add 1/3 cup milk and 1 teaspoon vanilla extract. Whisk confectioners' sugar into mixture until icing is smooth, 3 to 5 minutes. Pour icing over warm cake.