If you’re a peanut butter lover, this Peanut Butter Sheet Cake is pure heaven! Soft, moist, and full of nutty flavor, it’s topped with a creamy peanut butter frosting that melts in your mouth. Perfect for potlucks, birthdays, or any day you want a little extra comfort.
Why You’ll Love This Cake
- Rich Peanut Butter Flavor: Every bite is bursting with that creamy, nutty goodness.
- Simple to Make: No fancy tools — just mix, bake, and frost.
- Crowd-Pleaser: This 9×13-inch cake serves a group and stores beautifully.
Ingredients
For the Cake:
- 2 cups all-purpose flour
- 2 teaspoons baking powder
- 1/2 teaspoon baking soda
- 1/2 teaspoon salt
- 1/2 cup unsalted butter, softened
- 1 cup creamy peanut butter
- 1 cup granulated sugar
- 1 cup packed brown sugar
- 2 large eggs
- 1 teaspoon vanilla extract
- 1 cup buttermilk
For the Frosting:
- 1/2 cup unsalted butter, softened
- 1/2 cup creamy peanut butter
- 3 cups powdered sugar
- 1/4 cup milk
- 1 teaspoon vanilla extract
Instructions
Step 1: Preheat the Oven
Preheat your oven to 350°F (175°C). Grease and flour a 9×13-inch baking pan.
Step 2: Mix the Dry Ingredients
In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
Step 3: Cream the Butter and Sugars
In a large mixing bowl, beat the butter, peanut butter, granulated sugar, and brown sugar until light and fluffy.
Step 4: Add the Wet Ingredients
Beat in the eggs one at a time, then stir in the vanilla extract.
Step 5: Combine Everything
Gradually add the dry ingredients to the creamed mixture, alternating with the buttermilk. Mix until just combined — don’t overmix.
Step 6: Bake
Pour the batter into the prepared pan and smooth the top. Bake for 30–35 minutes, or until a toothpick inserted in the center comes out clean.
Step 7: Cool
Let the cake cool completely in the pan on a wire rack before frosting.
Make the Frosting
In a large bowl, beat together butter and peanut butter until smooth. Gradually add powdered sugar, milk, and vanilla extract. Beat until the frosting is fluffy and spreadable.
Spread evenly over the cooled cake, slice, and enjoy!
Recipe Tips
- For an extra peanut punch, sprinkle chopped peanuts or mini peanut butter chips on top.
- Make it chocolatey: Add a drizzle of melted chocolate or a dusting of cocoa powder.
- Store leftovers covered at room temperature for up to 3 days or in the fridge for up to 5 days.
Recipe Details
Prep Time: 20 minutes
Cook Time: 30–35 minutes
Total Time: 50–55 minutes
Servings: 12
Calories: ~450 kcal per serving
Meet the Creator
Hi, I’m Emily! I love creating delicious, approachable recipes that bring joy to family meals. Join me for more easy, comforting dishes made with love.