If you’re a fan of rich, creamy desserts with a nostalgic twist, get ready to fall head over heels for Peanut Butter Sheet Cake! This indulgent treat combines all the best things about classic cake and everyone’s favorite pantry staple—peanut butter—into one easy, flavorful, and utterly comforting dessert. Sheet cakes have a humble way of bringing us together, whether it’s for a family potluck, a birthday celebration, or a quick weeknight treat. Did you know that the love for peanut butter runs so deep in America that it’s celebrated with its own holiday each year? That’s just a sweet reminder of why this cake hits all the right notes!
What makes this dessert truly special isn’t just its irresistible taste but how simple it is to make. You don’t need any fancy equipment or tricky techniques—just a few pantry-friendly ingredients and a love for bold, satisfying flavors. It’s fast enough for last-minute guests and loved by adults and kids alike. If you’ve tried my Chocolate Texas Sheet Cake, you’ll find Peanut Butter Sheet Cake just as easy, but with a rich, nutty twist that’ll have your family asking for seconds. Let’s get baking and spread a little peanut buttery joy!
What is Peanut Butter Sheet Cake?
Now, what exactly is a Peanut Butter Sheet Cake? The name pretty much says it all, doesn’t it? Imagine a soft, moist cake, baked flat in a big pan, and loaded up with creamy peanut butter flavor. It’s like your favorite childhood peanut butter sandwich—just sweeter and way more fun! Who invented this tasty creation? Maybe someone with peanut butter on their mind and a hungry crowd to feed—after all, the way to a man’s heart (or anyone’s, really) is through the stomach. Whether you’re a lifelong peanut butter fan or just peanut butter curious, you won’t regret baking up this crowd-pleaser. Give it a try and watch smiles appear!
Why You’ll Love This
There’s so much to love about a Peanut Butter Sheet Cake—it’s almost impossible to pick just a few highlights! First, the unbeatable peanut butter flavor shines in both the fluffy cake and the luscious frosting, giving you a double dose of creamy, nutty goodness in every bite. Second, making this cake at home is seriously budget-friendly. Sheet cakes are made to feed a crowd without breaking the bank, especially when you skip bakery prices and whip up your own. Finally, the toppings take this dessert over the top! Smooth, sweet peanut butter frosting melts right onto the warm cake, while a sprinkle of chopped nuts or chocolate chips offers the perfect finishing touch.
If you loved my classic Chocolate Sheet Cake, this peanut butter twist is sure to wow you, too. Whether you’re baking for a party or treating your family, this recipe guarantees full bellies and happy hearts. Ready to satisfy your sweet tooth? Let’s get started!
How to Make
Quick Overview
Peanut Butter Sheet Cake is a breeze to make, even if you’re not a baking pro. With a simple cake base (thanks to boxed yellow cake mix) and a fuss-free peanut butter frosting, this dessert comes together in under an hour. The straightforward steps mean you get maximum flavor for minimal effort, and serving is easy thanks to the sheet cake style! The final cake is tender, rich, and drenched in creamy frosting—perfect for a cozy night in or a festive gathering.
Ingredients
- 1 box yellow cake mix
- 4 eggs
- 1/2 cup softened butter
- 1 cup water
- 1/2 cup creamy peanut butter
- 3 cups confectioners’ sugar
- 1/2 cup creamy peanut butter for frosting
- 1/2 cup softened butter for frosting
- 2 or more tablespoons milk for frosting
- 1 teaspoon pure vanilla extract
Step-by-Step
- Preheat your oven to 350°F (175°C). Grease a rimmed jelly roll pan or a standard sheet cake pan (typically 15×10 inches).
- In a large mixing bowl, combine the yellow cake mix, eggs, 1/2 cup softened butter, water, and 1/2 cup creamy peanut butter. Beat until smooth and creamy, about 2-3 minutes.
- Pour the batter into your prepared sheet pan, spreading it out evenly.
- Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean. Be careful not to overbake—sheets cakes bake quickly!
- While the cake is baking, start preparing the frosting. In another bowl, beat together 1/2 cup softened butter and 1/2 cup creamy peanut butter until smooth.
- Add in the confectioners’ sugar and vanilla extract. Gradually beat in the milk, one tablespoon at a time, until the frosting is creamy and spreadable.
- Once the cake is done, let it cool for about 10 minutes. Spread the peanut butter frosting evenly over the slightly warm cake, so it glides on like silk.
- Sprinkle with chopped peanuts, mini chocolate chips, or a dusting of extra confectioners’ sugar if desired.
- Slice, serve, and enjoy!
What to Serve Peanut Butter Sheet Cake With
Peanut Butter Sheet Cake pairs beautifully with a variety of sides and drinks to create an unforgettable dessert experience. Try serving slices with a tall, icy glass of cold milk—the classic peanut butter and milk combo never goes out of style! If you want something richer, a scoop of vanilla or chocolate ice cream alongside each slice balances the cake’s creamy filling. Fresh fruit, such as sliced bananas or strawberries, adds a refreshing contrast that lightens up each bite. For an extra festive touch, drizzle with a little chocolate sauce or a swirl of caramel. Whether you serve it as part of a potluck spread or as the grand finale of a family meal, this cake shines alongside simple, complementary treats.
Top Tips for Perfecting
- For a lighter cake, you can substitute applesauce for half the butter in the batter.
- Want to make it gluten-free? Use your favorite gluten-free yellow cake mix.
- When mixing the batter, be careful not to overbeat, which can make the cake dense.
- Add mini chocolate chips or chopped peanuts to the batter for texture and flavor.
- Always frost the cake while it’s still slightly warm—this helps the frosting spread easily and gives it that signature glossy finish.
- Don’t overbake! Sheet cakes cook fast. Check it at 18 minutes.
- Feeling adventurous? Swirl in a little jelly to the frosting for a playful PB&J effect.
Storing and Reheating Tips
To keep your Peanut Butter Sheet Cake tasting fresh:
- Store leftovers in an airtight container at room temperature for up to 2 days.
- For longer storage, refrigerate the cake (well wrapped) for up to 5 days. Let it come to room temperature before serving for the best texture.
- To freeze, wrap individual slices tightly in plastic wrap, then place in a freezer-safe bag or container. Freeze for up to 2 months.
- Thaw slices overnight in the fridge or at room temperature for a few hours.
- For that just-baked taste, microwave slices for 10-15 seconds before serving. This softens the frosting and brings out the cake’s irresistible richness.
FAQs
How can I make this recipe nut-free?
If you need a nut-free version, try using sunflower seed butter as a substitute in both the batter and frosting.
Can I make this cake ahead of time?
Absolutely! Bake the cake a day in advance, cool, and store tightly wrapped. For the freshest taste, frost just before serving.
What kind of yellow cake mix should I use?
Any standard box of yellow cake mix works well—feel free to use your favorite brand, regular or gluten-free.
Can I use chunky peanut butter?
Yes, but keep in mind your frosting and cake will have extra texture. If you prefer smooth, stick to creamy peanut butter.
Is it possible to halve the recipe?
Definitely! Bake it in a 9×13-inch pan and check for doneness a bit earlier since the cake will be thicker.
Conclusion
Peanut Butter Sheet Cake is proof that the simplest recipes often bring the most joy. From busy weeknights to big celebrations, this cake offers all the rich flavor and creamy comfort you crave, without any complicated steps. It’s budget-friendly, quick to make, and endlessly adaptable to suit your family’s tastes. Be sure to try out different toppings and serving ideas to make it your own, and don’t forget to check out my other sheet cake recipes for more inspiration. Get ready to serve up smiles—happy baking!

Peanut Butter Sheet Cake
Equipment
- Mixing Bowl
- Sheet Cake Pan
Ingredients
Cake Ingredients
- 1 box yellow cake mix
- 4 large eggs
- 1/2 cup softened butter
- 1 cup water
- 1/2 cup creamy peanut butter
Frosting Ingredients
- 3 cups confectioners' sugar
- 1/2 cup creamy peanut butter for frosting
- 1/2 cup softened butter for frosting
- 2 tablespoons milk for frosting Add more if needed to reach desired consistency.
- 1 teaspoon pure vanilla extract
Instructions
- Preheat your oven to 350°F (175°C). Grease a rimmed jelly roll pan or a standard sheet cake pan (typically 15×10 inches).
- In a large mixing bowl, combine the yellow cake mix, eggs, 1/2 cup softened butter, water, and 1/2 cup creamy peanut butter. Beat until smooth and creamy, about 2-3 minutes.
- Pour the batter into your prepared sheet pan, spreading it out evenly.
- Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean. Be careful not to overbake—sheet cakes bake quickly!
- While the cake is baking, start preparing the frosting. In another bowl, beat together 1/2 cup softened butter and 1/2 cup creamy peanut butter until smooth.
- Add in the confectioners' sugar and vanilla extract. Gradually beat in the milk, one tablespoon at a time, until the frosting is creamy and spreadable.
- Once the cake is done, let it cool for about 10 minutes. Spread the peanut butter frosting evenly over the slightly warm cake.
- Sprinkle with chopped peanuts, mini chocolate chips, or a dusting of extra confectioners’ sugar if desired.
- Slice, serve, and enjoy!