If you’re on the lookout for a crowd-pleasing dessert that offers pure nostalgia and unbeatable peanut flavor, Peanut Butter Sheet Cake with Peanut Butter Frosting is your answer. Imagine a tender, supremely moist cake infused with the rich, comforting essence of peanut butter, crowned with a thick, decadent layer of fudge-like peanut butter frosting that brings every bite to a dreamy finish. This recipe is a guaranteed hit at potlucks, birthdays, or any gathering where dessert lovers unite. It’s big enough to feed a crew and sure to win hearts with its melt-in-your-mouth texture and creamy peanut punch.
Ingredients You’ll Need
Making this Peanut Butter Sheet Cake with Peanut Butter Frosting is all about simple, straightforward ingredients, each playing its part in building the cake’s soft crumb, lush sweetness, and swoon-worthy frosting. Here’s what you’ll need, plus a few helpful notes about what each one does for your cake.
- All-purpose flour: This is the sturdy framework of the cake, ensuring just the right amount of structure while keeping the crumb tender.
- Granulated sugar: Sweetens the cake and helps create the moist, soft texture we love.
- Baking soda: Gives the cake its lift and fluffiness—don’t skip it!
- Salt: Makes all the flavors pop, balancing out the sweetness and peanut butter richness.
- Water: Keeps the batter pourable and helps dissolve the peanut butter and butter in the heating step.
- Unsalted butter: Delivers unbeatable richness to both the cake and frosting—go for real butter for best flavor.
- Creamy peanut butter: The star ingredient! Choose a no-stir, shelf-stable peanut butter for perfect texture.
- Buttermilk: Reacts with baking soda for a soft crumb and just a hint of tang that complements the peanut butter.
- Large eggs: Bind everything together and provide structure for that lovely sheet cake rise.
- Vanilla extract: Rounds out the flavors and pairs perfectly with peanut butter.
- Milk (or buttermilk) for frosting: Adds creaminess, and you can use buttermilk for extra tang if you like.
- Powdered sugar: Gives the frosting its fluffy, smooth consistency you’ll want to eat by the spoonful.
How to Make Peanut Butter Sheet Cake with Peanut Butter Frosting
Step 1: Prepare Your Baking Pan and Preheat
Start by preheating your oven to 350°F (175°C) so it’s ready when your batter is mixed. Generously grease a 9×13-inch baking pan with butter or nonstick spray—this ensures your Peanut Butter Sheet Cake with Peanut Butter Frosting will release easily and keep those beautiful edges intact.
Step 2: Mix the Dry Ingredients
In a large mixing bowl, whisk together the flour, sugar, baking soda, and salt. This quick step ensures your leavening is distributed evenly, giving the cake a super-soft crumb from end to end.
Step 3: Make the Warm Peanut Butter Mixture
Set a saucepan on medium heat, and combine the water, unsalted butter, and creamy peanut butter. Stir constantly—once everything melts together into a smooth, glossy mixture, immediately remove it from the heat. This warming step helps the peanut butter blend seamlessly into the batter, guaranteeing big flavor in every bite.
Step 4: Combine Wet and Dry
Pour the warm peanut butter mixture over your dry ingredients and stir gently just until combined. The fragrance as peanut butter hits the flour is absolute heaven!
Step 5: Mix Eggs, Buttermilk, and Vanilla
In a separate bowl, whisk together the buttermilk, eggs, and vanilla extract. Pour this into the batter and stir until your mixture is completely smooth and uniform. Don’t overmix—just enough to bring everything together for a delicate, tender cake.
Step 6: Bake Your Cake
Transfer the batter into your prepared pan, smoothing the top with a spatula. Bake for 25–30 minutes or until the cake is golden, and a toothpick inserted into the center comes out clean. Resist the urge to open the oven too often—the even heat helps your cake rise perfectly.
Step 7: Make the Peanut Butter Frosting
While the cake bakes, melt butter and creamy peanut butter in a saucepan over medium heat. Stir in the milk (or buttermilk) and bring it just to a gentle simmer—this helps create that fudgy, glossy icing texture. Take the pan off the heat, whisk in the vanilla, and gradually add the powdered sugar. Mix until completely smooth, creamy, and irresistible.
Step 8: Frost While Warm
When your cake comes out of the oven, don’t wait for it to cool entirely—spread the peanut butter frosting over the warm cake right away. The gentle warmth encourages the frosting to melt slightly into the top, making every slice moist and luscious. Let the cake cool completely before slicing for clean, beautiful portions.
How to Serve Peanut Butter Sheet Cake with Peanut Butter Frosting
Garnishes
For an extra-special touch, sprinkle roasted peanuts or peanut butter chips over the warm frosting, or drizzle a little melted chocolate for a dessert that looks as good as it tastes. For a fun twist, a dusting of flaky sea salt brings out the sweetness and intensifies all the flavors in the Peanut Butter Sheet Cake with Peanut Butter Frosting.
Side Dishes
This sheet cake is rich and satisfying, so simple sides make the perfect pairing. Try serving with fresh berries, a scoop of vanilla or chocolate ice cream, or a tall glass of cold milk. For adults, a dark roast coffee or café au lait elevates every bite.
Creative Ways to Present
Transform leftovers into layered dessert parfaits with whipped cream and chopped peanuts, or use cookie cutters to create playful cake shapes for a party platter. You can also slice the Peanut Butter Sheet Cake with Peanut Butter Frosting into small squares, place them in cupcake liners, and serve as “cake bites” for potlucks and picnics—guaranteed to disappear fast.
Make Ahead and Storage
Storing Leftovers
Cover your cake tightly with plastic wrap or store slices in an airtight container at room temperature for up to three days. The frosting helps keep things moist, and the flavors only get dreamier after a day of rest.
Freezing
If you’re making Peanut Butter Sheet Cake with Peanut Butter Frosting ahead, allow it to cool completely, then wrap individual slices tightly in plastic wrap and foil before freezing. It stays delicious for up to three months—just thaw overnight on the counter for best texture.
Reheating
For that just-baked feel, warm slices gently in the microwave for 10 to 15 seconds. The frosting gets a touch soft and gooey, making every bite taste freshly baked. If the cake has been in the fridge, let it come to room temperature before enjoying for the best texture.
FAQs
Can I use natural peanut butter instead of regular creamy peanut butter?
You can, but for the most reliable results, stick to no-stir, shelf-stable creamy peanut butter. Natural peanut butter tends to separate and can make the cake and frosting less smooth and slightly oily. If you do try it, stir thoroughly and expect a slightly different texture.
How do I know when my Peanut Butter Sheet Cake with Peanut Butter Frosting is done baking?
The cake is ready when the center springs back lightly to the touch, and a toothpick inserted in the very middle comes out clean or with just a few crumbs—start checking around the 25-minute mark to prevent overbaking.
Can this recipe be doubled or halved?
Absolutely! If making a big batch for a party, double the recipe and bake it in a half-sheet pan, adjusting bake time as needed. For smaller gatherings, halve all the ingredients and use an 8×8-inch pan, but start checking for doneness at 20 minutes.
Is there a way to make this cake gluten-free?
Yes! Swap the all-purpose flour for your favorite 1:1 gluten-free baking flour blend. Check that your other ingredients are gluten-free as well. The texture may vary slightly, but you’ll still get a moist, flavorful result.
Can I add chocolate to this cake?
Why not? Stir mini chocolate chips into the batter before baking, add a drizzle of chocolate over the finished frosting, or swirl in some melted chocolate to the top for a peanut butter-chocolate combo that will have everyone swooning!
Final Thoughts
If you’re searching for a treat that brings comfort, joy, and a whole lot of peanut butter love, look no further than Peanut Butter Sheet Cake with Peanut Butter Frosting. It’s easy, it’s luscious, and it’s guaranteed to crowd-please. Give it a try—you might just find your new signature dessert!
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Peanut Butter Sheet Cake with Peanut Butter Frosting Recipe
- Total Time: 45 minutes
- Yield: 16–20 servings
- Diet: Vegetarian
Description
This rich and tender Peanut Butter Sheet Cake delivers pure peanut butter bliss in every bite, topped with a thick, velvety peanut butter frosting. Baked in a 9×13″ pan and sized perfectly to serve a crowd, this easy, homemade cake is the perfect treat for potlucks, birthdays, or any time you crave a peanut butter dessert.
Ingredients
Cake
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 3/4 tsp baking soda
- 1/2 tsp salt
- 1 cup water
- 3/4 cup unsalted butter
- 1/2 cup creamy peanut butter
- 1/2 cup buttermilk
- 2 large eggs
- 1 tsp vanilla extract
Frosting
- 1/2 cup unsalted butter
- 1/2 cup creamy peanut butter
- 1/4 cup milk (or buttermilk)
- 1 tsp vanilla extract
- 4 cups powdered sugar
Instructions
- Prepare the Oven and Pan: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking pan to prevent sticking and set aside.
- Combine Dry Ingredients: In a large mixing bowl, whisk together the flour, granulated sugar, baking soda, and salt until evenly blended.
- Make the Peanut Butter Mixture: In a saucepan over medium heat, combine water, unsalted butter, and creamy peanut butter. Stir constantly until the mixture is melted, smooth, and fully combined. Remove from heat.
- Mix Wet and Dry Ingredients: Pour the warm peanut butter mixture into your bowl with the dry ingredients. Stir until just combined.
- Add Remaining Wet Ingredients: In a separate small bowl, whisk together the buttermilk, eggs, and vanilla extract. Add this mixture to the batter and stir until smooth and well incorporated, but do not overmix.
- Bake the Cake: Pour the batter into the prepared pan. Bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean or with just a few moist crumbs.
- Make the Frosting: While the cake bakes, melt unsalted butter and creamy peanut butter together in a saucepan over medium heat. Stir in the milk (or buttermilk) and bring just to a simmer, then remove from heat.
- Finish the Frosting: Whisk in the vanilla extract and gradually add the powdered sugar, whisking until the frosting is smooth, creamy, and free of lumps.
- Frost the Cake: Spread the frosting over the warm cake immediately after it comes out of the oven, smoothing it into an even layer.
- Cool and Serve: Allow the cake and frosting to cool completely in the pan before slicing and serving for optimal texture and flavor.
Notes
- The frosting sets as the cake cools, so spread it while both are still warm for the best results.
- For extra texture, try sprinkling chopped peanuts over the frosted cake.
- This cake stores well, covered, at room temperature for up to 3 days or refrigerated for up to 5 days.
- You can substitute whole milk for buttermilk if needed, though buttermilk adds tang and tenderness.
- Prep Time: 20 minutes
- Cook Time: 25 minutes
- Category: Desserts
- Method: Baking
- Cuisine: American