Peanut Butter Sheet Cake with Fluffy Chocolate Frosting Recipe

Ingredients

Peanut Butter Sheet Cake

• 2 cups all purpose flour (298g)
• 2 cups granulated sugar (396g)
• 0.5 teaspoon baking soda
• 0.25 teaspoon salt
• 1 cup water (250ml)
• 1.5 sticks unsalted butter (170g, divided)
• 0.25 cup canola oil (60ml)
• 1 cup creamy peanut butter (250g, divided)
• 2 whole eggs
• 0.5 cup buttermilk (120ml)
• 1 teaspoon pure vanilla extract

Fluffy Chocolate Buttercream Frosting

• 1 12-ounce bag chocolate chips
• 1.25 sticks unsalted butter (176g)
• 2 cups confectioners sugar (250g)
• 1 teaspoon pure vanilla extract
• 0.25 cup heavy cream (60ml)

Instructions

Peanut Butter Sheet Cake

1. Preheat oven to 350°F. Grease a 9x13 inch baking pan.
2. In a large bowl, whisk together flour, sugar, baking soda, and salt.
3. In a saucepan, combine water, 1½ sticks butter, canola oil, and ¾ cup peanut butter. Heat until butter melts and mixture is warm.
4. Pour warm mixture over flour mixture and stir until combined.
5. In a small bowl, whisk together eggs, buttermilk, and vanilla extract.
6. Add egg mixture to flour mixture and stir until smooth.
7. Pour batter into prepared pan.
8. Bake for 35-40 minutes, or until a toothpick inserted in the center comes out clean.
9. While cake is baking, make the peanut butter filling: Mix remaining ¼ cup peanut butter with a spoon until spreadable.
10. Remove cake from oven and immediately spread peanut butter filling over warm cake.
11. Allow cake to cool slightly before frosting.

Fluffy Chocolate Buttercream Frosting

1. In a microwave-safe bowl, combine chocolate chips and 1¼ sticks butter. Microwave in 30-second intervals, stirring between each, until melted and smooth.
2. Remove from microwave and cool slightly.
3. In a large bowl, beat confectioners sugar, vanilla extract, and heavy cream until combined.
4. Fold chocolate mixture into sugar mixture until smooth.
5. Spread frosting over cooled cake.