Grandpa’s Favorite Treat – Peanut Butter Sheet Cake with Creamy Frosting

The warm, nutty goodness of peanut butter and a thick, melt-in-your-mouth frosting. A family tradition that celebrates love and peanut butter, just the way Grandpa liked it.

Introduction
Every year, without fail, Grandpa requested the same special treat for his birthday: a warm peanut butter sheet cake, fresh out of the oven, with creamy frosting poured on top while it was still hot. The frosting would melt into the soft, nutty cake, creating the perfect combination of flavors. It became a family tradition, a way for us to celebrate love, laughter, and of course, peanut butter! 💖🥄

Ingredients
For the Cake:

  • 2 cups flour
  • 2 cups sugar
  • 1 tsp baking soda
  • 1/2 tsp salt
  • 1 cup water
  • 1/2 cup butter
  • 1/2 cup creamy peanut butter
  • 2 eggs
  • 1/2 cup buttermilk
  • 1 tsp vanilla

For the Frosting:

  • 1/2 cup butter
  • 1/2 cup creamy peanut butter
  • 1/3 cup milk
  • 3 cups powdered sugar
  • 1 tsp vanilla

Step-by-Step Preparation

🍰 Preheat the oven: Set your oven to 175°C (350°F) and grease a sheet pan.

🧈 Mix the dry ingredients: In a large bowl, combine the flour, sugar, baking soda, and salt.

🔥 Prepare the wet mixture: In a saucepan, bring the water, butter, and peanut butter to a boil. Once melted, pour the mixture into your dry ingredients.

🥚 Add the eggs and buttermilk: Stir in the eggs, buttermilk, and vanilla until the batter is smooth.

⚡ Bake the cake: Pour the batter into the prepared sheet pan and bake for 20–25 minutes, or until a toothpick comes out clean.

🧁 Make the frosting: In a saucepan, melt the butter and peanut butter together. Add the milk and vanilla, then whisk in the powdered sugar until smooth.

💧 Frost the cake: As soon as the cake comes out of the oven, pour the frosting over the warm cake and let it soak in.

Preparation Time

  • 15 minutes prep
  • 25 minutes baking

Mistakes to Avoid

  1. Waiting too long to frost – The frosting needs to be poured on while the cake is still hot so it melts perfectly into the cake.
  2. Overbaking – Keep an eye on the cake so it stays soft and moist. It should be tender, not dry.
  3. Skipping the buttermilk – This ingredient adds moisture and tenderness to the cake, making it extra soft.

Serving Tip
Serve this cake warm with a cold glass of milk or a scoop of vanilla ice cream for the ultimate treat! 🍦🥛