If you’re a peanut butter lover, this Peanut Butter Sheet Cake with Peanut Butter Frosting is your ultimate dessert dream. Imagine a moist, tender cake infused with rich peanut flavor, topped with a creamy, buttery frosting that melts in your mouth. Every bite delivers the perfect balance of sweetness, nuttiness, and comfort—making it a must-bake for birthdays, potlucks, or weekend indulgences.
This sheet cake is not only decadent but also easy to make. The simple mixing method and large pan yield a crowd-pleasing dessert with minimal effort. Its soft crumb and creamy frosting make it perfect for slicing into generous squares, serving family and friends, or packing for gatherings. The combination of creamy peanut butter in both the cake and frosting ensures a flavor explosion that peanut enthusiasts will adore.
Why You’ll Love This Recipe
- Peanut Butter Heaven: Both the cake and frosting are loaded with peanut flavor.
- Soft & Moist Texture: Tender cake that stays moist even a day later.
- Party-Friendly: Large sheet pan makes it easy to serve many guests.
- Easy to Make: Simple steps with pantry-friendly ingredients.
- Make-Ahead Friendly: Frosting and cake can be prepared in advance.
- Kid-Approved: Sweet, creamy, and irresistibly rich—perfect for children and adults alike.
Ingredient Breakdown
Creamy Peanut Butter (for cake & frosting): The star ingredient providing rich, nutty flavor and moist texture.
Unsalted Butter (for cake & frosting): Adds richness, tenderness, and helps the frosting achieve a smooth, spreadable consistency.
Granulated Sugar (2 cups for cake): Sweetens the cake while promoting a tender crumb.
Eggs (4 large): Bind ingredients together and add structure to the cake.
Vanilla Extract: Enhances the peanut flavor and adds aromatic depth.
All-Purpose Flour: Provides structure for a soft, tender cake that holds up to frosting.
Baking Powder & Baking Soda: Work together to leaven the cake, ensuring a light, airy texture.
Salt: Balances sweetness and enhances the peanut flavor.
Buttermilk: Adds moisture, tenderness, and a subtle tang that balances the sweetness.
Powdered Sugar (for frosting): Creates a smooth, creamy frosting that’s sweet but light.
Milk (for frosting): Adjusts the consistency to make the frosting spreadable but still fluffy.
Pro Tips
- Room Temperature Ingredients: Ensure butter, eggs, and peanut butter are at room temperature for even mixing.
- Alternate Wet & Dry Ingredients: When adding flour and buttermilk, alternate them to prevent overmixing and maintain a tender crumb.
- Don’t Overbake: Check the cake at 25 minutes to prevent it from drying out. A toothpick should come out clean with a few moist crumbs.
- Smooth Frosting: Beat butter and peanut butter thoroughly before adding powdered sugar to avoid lumps.
- Chill for Neat Slices: Refrigerate the frosted cake for 20–30 minutes before slicing to keep squares clean and intact.
Ingredient Swaps or Variations
- Nut Butters: Swap peanut butter for almond butter, cashew butter, or sunflower seed butter for a different nutty flavor.
- Chocolate Swirl: Add melted chocolate to the batter or swirl chocolate into the frosting for a marbled effect.
- Gluten-Free Option: Substitute a 1:1 gluten-free flour blend to make the cake suitable for gluten-sensitive eaters.
- Honey or Maple: Replace part of the sugar with honey or maple syrup for a unique flavor profile.
- Crunchy Twist: Fold in chopped peanuts or peanut butter cups into the batter for texture and extra indulgence.
Serving Suggestions
Serve this peanut butter sheet cake chilled or at room temperature, cut into generous squares. For an elevated presentation, drizzle chocolate ganache over the frosting or sprinkle with crushed peanuts. Pair with a glass of cold milk, hot coffee, or even a scoop of vanilla ice cream for a complete dessert experience. Ideal for birthdays, celebrations, or a simple indulgent treat on a weekend afternoon.
Make Ahead + Storage Tips
- Make Ahead: Bake the cake a day ahead and store unfrosted in an airtight container. Frost just before serving for the freshest texture.
- Storage: Keep the frosted cake covered at room temperature for up to 3 days, or refrigerate for up to 5 days.
- Freezing: Wrap cooled, unfrosted cake tightly in plastic wrap and foil, freeze for up to 2 months. Thaw overnight and frost before serving.
- Reheating: For slightly warm slices, microwave small squares for 10–15 seconds.
Cultural or Historical Notes
Peanut butter, originally popularized in the early 20th century in the United States, has become a staple in American desserts. Sheet cakes have long been favored for their simplicity and ability to feed large groups. Combining the two in this Peanut Butter Sheet Cake creates a classic American treat that’s perfect for modern celebrations, offering nostalgia with a convenient, easy-to-serve format.
Frequently Asked Questions (FAQ)
1. Can I use natural peanut butter instead of creamy?
Yes, but ensure it’s well-stirred and smooth. Natural peanut butter may slightly affect the cake’s texture.
2. Can this cake be made into a layer cake?
Absolutely! Bake in two 9×13-inch pans, stack, and frost between layers for a layered peanut butter delight.
3. How can I make the frosting lighter?
Add extra milk or a bit of whipped cream to make the frosting fluffier and less sweet.
4. Is it possible to make this cake dairy-free?
Yes! Use plant-based butter, non-dairy milk, and vegan powdered sugar to make it dairy-free.
5. Can I add chocolate chips to the batter?
Definitely! Fold in 1–2 cups of chocolate chips for a chocolate-peanut twist.
Peanut Butter Sheet Cake with Peanut Butter Frosting
Ingredients
Equipment
Method
- Preheat your oven to 350°F (175°C). Grease and flour a 13×18-inch sheet pan.
- In a large bowl, cream together the peanut butter, butter, and sugar until light and fluffy. Add eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
- In another bowl, whisk together flour, baking powder, baking soda, and salt.
- Gradually add the dry ingredients to the peanut butter mixture, alternating with buttermilk, starting and ending with the dry ingredients. Mix until just combined.
- Pour the batter into the prepared sheet pan and smooth the top. Bake for 25–30 minutes, or until a toothpick inserted into the center comes out clean. Let cool completely in the pan.
- In a medium bowl, beat together the peanut butter and butter until smooth. Gradually add powdered sugar and milk, mixing until creamy. Stir in the vanilla extract.
- Once the cake has cooled, spread the peanut butter frosting evenly over the top.
- Cut into squares and enjoy!
