Home › Desserts › Peanut Butter Sheet Cake

Peanut Butter Sheet Cake

Forget chocolate! This peanut butter sheet cake is a soft, moist, and wonderfully scrumptious dessert you don’t want to miss.

I’m a huge fan of all things peanut butter. So a cake with it in the sponge and the frosting? That’s my jam!

It’s tender, nutty, and perfectly sweet. Plus, it’s a breeze to make! You can have it ready to devour in just over an hour.

Soft, moist and nutty homemade peanut butter sheet cake
WANT TO SAVE THIS RECIPE?
Enter your email below & we'll send it straight to your inbox.

Peanut Butter Sheet Cake

This peanut butter sheet cake is an absolute must-try for all peanut butter lovers out there.

It’s like a Texas sheet cake, but reimagined with a nutty twist. 

And if you think the combination of peanut butter cake and peanut butter frosting is too much, think again. It’s devilishly delicious and perfectly balanced.

The best part? One recipe can serve up to two dozen slices. So it’s my new go-to way to feed a crowd (while avoiding a mountain of dishes!). 

And trust me, it’ll be a huge hit. I mean, who doesn’t love peanut butter?

Ingredients

Scroll to the bottom of the page for the full list with measurements.

For now, here’s the scoop on what you’ll need for this peanut butter sheet cake:

  • All-Purpose Flour: The foundation of the cake’s structure, providing a sturdy base for the other ingredients.
  • Granulated and Brown Sugar: White sugar adds sweetness to balance the rich peanut butter flavor. Brown sugar contributes caramel notes and extra moisture for a soft, tender crumb.
  • Baking Soda: The leavening agent that helps the cake rise to fluffy perfection.
  • Salt: Enhances and amplifies all the delicious flavors.
  • Unsalted Butter: Provides richness and keeps the cake moist and tender.
  • Creamy Peanut Butter and Water: The star ingredient that infuses the cake with nutty, creamy goodness. Add a little water for easy mixing.
  • Buttermilk: Adds a subtle tang and reacts with the baking soda for a light texture.
  • Eggs: Act as the glue holding everything together while adding richness and structure.
  • Vanilla Extract: Rounds out the flavours with a hint of sweet aroma.
  • Peanut Butter Frosting: A yummy blend of butter, peanut butter, milk, powdered sugar, and vanilla.
Peanut butter sheet cake in a 9x13 inch baking pan on a white marble table

How to Make Peanut Butter Sheet Cake

Are you ready to make the most dreamy sheet cake ever? Great! Just follow these easy steps:

1. PREP. Preheat the oven to 350 degrees Fahrenheit. Grease and flour a 9×13-inch pan.

2. MIX. In a large bowl, whisk the flour, sugars, baking soda, and salt.

3. BOIL. In a saucepan, boil the butter with the water, then turn off the heat and add the peanut butter, stirring constantly until smooth. Then, pour over the dry ingredients and mix well.

4. COMBINE. Whisk the buttermilk, eggs, and vanilla. Stir them into the batter until smooth.

5. BAKE. Pour the batter into the prepared pan and bake for 30-35 minutes or until a toothpick inserted comes out clean.

6. FROST. In a saucepan, simmer the butter, peanut butter, and milk until smooth. Remove from heat and stir in the powdered sugar and vanilla. Spread the frosting on the cooled cake.

7. SERVE. Let the cake cool, then slice, serve, and enjoy!

A piece of homemade peanut butter sheet cake with frosting on a white marble table

Recipe Tips and Tricks

Here are some tips to make your peanut butter sheet cake is a hit every time.

  • Don’t use natural peanut butter where the oil separates. It will make the cake greasy and unpleasant.
  • Thin out thick frosting. Gently mix in more milk, a tablespoon at a time, until it’s just right. You want it spreadable so it doesn’t ruin the cake.
  • Work fast. Once the frosting’s ready, spread it quickly over the cake. It thickens as it cools!
  • Jelly Roll Pan option. For a thinner cake, use a 15×10-inch jelly roll pan and bake at 350°F for 18-22 minutes.
  • Icing variations. Consider adding espresso or strong coffee to the icing for an extra flavor layer and to reduce sweetness.
  • Less sweet glaze. Halve the frosting recipe and use a bit more milk for a thinner, less sweet glaze.
  • Make it your own. Feel free to add mini chocolate chips to the sponge, a layer of jam under the frosting, or a swirl of melted chocolate over the top.
Peanut butter sheet cake topped with a smooth layer frosting

How to Store and Freeze

Like this yummy vanilla sheet cake, this peanut butter dream is a perfect make-ahead dessert.

You just need to know how to store it!

To Store: Store the cake or leftovers in an airtight container or wrap them in plastic wrap (in the baking pan). Keep it at room temperature for up to 3 days or refrigerate for up to a week. 

To Freeze: Chill the cake until the frosting is firm, then double wrap it in plastic and add a layer of foil. Freeze for up to 3 months.

WANT TO SAVE THIS RECIPE?
Enter your email below & we'll send it straight to your inbox.

More Peanut Butter Dessert Recipes

Chocolate-Covered Peanut Butter Balls
Peanut Butter Cheerio Bars
Peanut Butter Pudding
3-Ingredient Peanut Butter Cookies
Peanut Butter Balls with Rice Krispies

Peanut Butter Sheet Cake

Course: DessertCuisine: American
Servings

24

servings
Prep time

15

minutes
Cooking time

40

minutes
Calories

425

kcal

Forget chocolate! This peanut butter sheet cake is a soft, moist, and scrumptiously nutty dessert you don’t want to miss. Plus, it’s a breeze to make!

Ingredients

  • For the Cake:
  • 2 cups all-purpose flour

  • 1 cup granulated sugar

  • 1 cup brown sugar, packed

  • 1 teaspoon baking soda

  • 1 teaspoon salt

  • 1/2 cup unsalted butter

  • 1 cup water

  • 1/2 cup creamy peanut butter

  • 1/2 cup buttermilk

  • 2 large eggs

  • 1 teaspoon vanilla extract

  • For the Peanut Butter Frosting:
  • 3/4 cup unsalted butter

  • 2/3 cup creamy peanut butter

  • 6 tablespoons milk

  • 3 1/2 cups powdered sugar

  • 1 teaspoon vanilla extract

Instructions

  • Preheat the oven to 350 degrees Fahrenheit. Grease and flour a 9×13-inch baking pan.
  • In a large bowl, combine flour, sugars, baking soda, and salt. Set aside.
  • In a saucepan over medium heat, combine the butter and water. Bring to a boil, then remove from the heat, add the peanut butter, and stir until well blended.
  • Pour the peanut butter blend over the dry ingredients and mix until well combined.
  • In a small bowl, whisk the buttermilk, eggs, and vanilla until smooth. Add to the batter and mix until smooth.
  • Pour the batter into the prepared baking pan, spreading evenly, and bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.
  • While the cake cools, make the frosting. Combine the butter, peanut butter, and milk in a saucepan over medium heat and bring to a boil.
  • Remove from the heat and gradually stir in powdered sugar and vanilla until smooth.
  • Immediately spread the frosting over the warm cake. Then, let the cake and frosting cool before slicing. Serve and enjoy!

Notes

  • Use chunky peanut butter instead of creamy for a crunchy cake and frosting.
  • Frosting too thick? Add a little more milk, one tablespoon at a time, until it reaches your desired consistency.
Peanut Butter Sheet Cake

Did you like the recipe?

Click on a star to rate it!

Average rating 5 / 5. Vote count: 2

No votes so far! Be the first to rate this post.

Thanks!

Share on social media:

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

author avatar
Kim - InsanelyGood
Hey there! I'm Kim. I love running, cooking, and curling up with a good book! I share recipes for people who LOVE good food, but want to keep things simple :)

Leave a Comment