Ingredients

2 cups all-purpose flour

2 cups sugar

1/2 teaspoon baking soda

1/4 teaspoon salt

1 1/2 sticks (12 tablespoons) butter

1 cup water

1/2 cup peanut butter

1/4 cup vegetable oil

2 eggs

1/2 cup buttermilk

1 teaspoon vanilla extract

2 sticks (1 cup) butter, softened (for frosting)

3/4 cup peanut butter (for frosting)

3 cups confectioners’ sugar (for frosting)

3 to 4 tablespoons milk (for frosting)

2 tablespoons instant vanilla pudding mix (for frosting)

Instructions

Step 1: Preheat the oven to 350 degrees Fahrenheit. Grease a 10x15x1 inch jellyroll pan and set aside.

Step 2: In a large bowl, whisk together the flour, sugar, baking soda, and salt until well combined.

Step 3: In a medium saucepan, combine 1 1/2 sticks of butter and the water. Bring to a simmer, stirring occasionally until all the butter has melted.

Step 4: Whisk the 1/2 cup of peanut butter and the vegetable oil into the butter and water mixture. Pour this wet mixture into the flour mixture and stir to combine.

Step 5: In a separate bowl, whisk together the eggs, buttermilk, and vanilla extract. Stir this mixture into the flour batter until fully combined.

Step 6: Pour the batter into the prepared jellyroll pan, spreading it evenly.

Step 7: Bake for 22 to 26 minutes or until a toothpick inserted in the center comes out clean. Remove from the oven and allow the cake to cool completely.

Step 8: To make the frosting, use an electric mixer to beat the softened butter and peanut butter together until smooth and creamy.

Step 9: Add half of the confectioners’ sugar and half of the milk to the peanut butter mixture. Beat until smooth and well combined.

Step 10: Add the remaining confectioners’ sugar, milk, and the instant vanilla pudding mix. Continue beating until the frosting is smooth. Add a little more milk if the frosting is too thick.

Step 11: Spread the frosting evenly over the cooled cake. Slice and serve.

Tips & Variations

For a crunchier texture, sprinkle chopped roasted peanuts on top of the frosting before serving.

If you prefer a chocolate twist, add 1/2 cup of cocoa powder to the dry ingredients.

You can substitute buttermilk with regular milk mixed with 1 tablespoon of lemon juice or vinegar as a quick alternative.

Make sure the cake is fully cooled before frosting to prevent melting and sliding.

FAQs

Can I make this cake gluten-free?

Yes, you can substitute the all-purpose flour with a gluten-free flour blend that measures cup for cup. Make sure it contains xanthan gum for best texture.

Can I freeze the cake?

The cake can be frozen either unfrosted or frosted. Wrap tightly in plastic wrap and foil before freezing. Thaw overnight in the refrigerator and bring to room temperature before serving. Frosting may need gentle re-whipping if it separates after thawing.