Peanut Butter Sheet Cake with Marshmallow Frosting

Peanut butter lovers rejoice! This Peanut Butter Cake with Marshmallow Frosting is the dessert recipe of your dreams. A moist cake that’s full of peanut butter flavor- everyone needs a good sheet cake recipe box.

This Peanut Butter Cake is a great cake all on its own. Moist and full of peanut buttery (is that a word?) flavor, it will be sure to please everyone at your party or gathering. Unless, of course, they have a peanut allergy, then keep this bad boy far away from them!

It is also super easy to make, as it is a sheet cake versus a traditional peanut butter layer cake. We all know I am far from a great baker. LOL.

Peanut Butter Cake Ingredients

The cake itself is made from peanut butter and your usual cake mix ingredients. Most of them I’m sure you’ll be able to find right in your pantry.

Dry ingredients:

• all-purpose flour
• white sugar
• brown sugar
• baking soda
• baking powder
• fine sea salt

Wet ingredients:

• creamy peanut butter – I do not recommend using chunky peanut butter if you like a smooth cake. Of course, if you’d like a bit of added crunch, feel free to use it. Also I’m not a fan of using natural peanut butter for this cake. It’s generally not as sweet as say Jif or Skippy.
• milk 
• vanilla extract
• eggs 
• vegetable oil  

Peanut Butter Frosting Recipe

For my Peanut Butter Cake, I opted for an equally as delicious frosting: easy marshmallow frosting! I can see the peanut butter fans out there swooning while reading this cause yes, you are totally allowed to make just the frosting and eat it with a spoon. We won’t judge.

But hey, this is a lot of work, albeit pretty simple, for frosting, so if you don’t want to mess with it, sub in a tub of chocolate frosting, Chocolate Buttercream or even cream cheese frosting.

But I do have to tell you, the combination of peanut butter and marshmallow is out of this world and totally worth the extra time and effort. Plus, this frosting would also taste great on a chocolate mayonnaise cake too!

Marshmallow frosting ingredients:

• white sugar
• evaporated milk
• butter
• creamy peanut butter
• mini marshmallows
• vanilla extract

Peanut Butter Cake Recipe

Are you ready to start making the best peanut butter cake ever?

1. Preheat your oven and prep a 9×13 inch pan with cooking spray, set aside.
2. In a large mixing bowl, cream peanut butter and sugar until light and fluffy- this does take a while, some folks skip this step and it is super important. Make sure to scrape the sides and bottom of the bowl and then add in the wet ingredients.
3. Sift the dry ingredients before adding to the peanut butter mixture, this ensures they are well mixed without having to overmix the batter and potentially land a dry cake. Mix until there are just no dry spots remaining.
4. Pour batter into the prepared pan and bake until it passes the toothpick test.

Top It

Usually you would wait until a cake is cooled to room temperature before you frost it. However with this ultimate peanut butter cake you do just the opposite. I’ve found that the best thing to do is to pour the hot frosting right on top of the hot cake and gets all gooey.

No fancy offset spatula or disposable piping bag needed for this delicious cake, just simply pour over the frosting and dress is up with whichever toppings you’d like.

No matter which way you dress it up, or don’t, grab a cold glass of milk and enjoy your sweet treat!

Our favorites include:

• Honey roasted peanuts
• Chopped Reeses Peanut Butter Cups
• Melted chocolate
• Chocolate chips or peanut butter chips
• Chocolate ganache
• Plain- the cake and the frosting are that good that you don’t need much more!

More peanut butter desserts!

• Whipped Peanut Butter Dip
• Single Serving Peanut Butter Cookie Dough
• Peanut Butter and Chocolate Cookie Sandwiches
• No Bake Peanut Butter Cheesecake
• Peanut Butter and Jelly Rice Krispie Treats
• Peanut Butter Pretzels Bites

Soft Peanut Butter Cookies

Soft and chewy Peanut Butter Cookies made from scratch with a few pantry essentials.

See The Recipe!

No Bake Peanut Butter Pie Recipe

Decadent and silky, this easy Peanut Butter Pie is a no bake dessert recipe that utilizes only 8 ingredients to make the crust, filling, and toppings!

See The Recipe!

Buckeye Candy

If you love a dessert with peanut butter and chocolate you will adore this Classic Buckeye Candy recipe. Perfect for the holidays!

See The Recipe!

Instant Pot Peanut Butter Cheesecake

Instant Pot Peanut Butter Cheesecake is a rich and creamy cheesecake with a graham cracker crust, layer of chocolate and topped with peanut butter and chocolate chips.

Peanut Butter Cake with Marshmallow Frosting

4.91 from 11 votes

Peanut Butter Cake with Peanut Butter Marshmallow Frosting and honey roasted peanuts is an easy cake recipe that is moist and perfect for any occasion.

Prep Time: 20 minutes mins

Cook Time: 30 minutes mins

Cooling Time: 1 hour hr

Total Time: 1 hour hr 50 minutes mins

Servings: 16 slices

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Equipment

• 9×13 Baking Dish
• Heavy Bottom Saucepan
• Whisk
• Stand Mixer
• Toothpicks
• Sifter

Ingredients

• 1 cup granulated sugar
• 1 cup brown sugar- lightly packed
• 1 cup smooth peanut butter
• 1 ¼ cup milk
• 2 teaspoons vanilla
• 2 eggs
• ¼ cup vegetable oil
• 2 ¼ cup flour
• 1 teaspoon baking soda
• 1 teaspoon baking powder
• ¼ tsp salt

Marshmallow Frosting:

• 2/3 cup sugar
• 1/3 cup evaporated milk
• 1 tablespoon butter
• 3/4 cup creamy peanut butter
• 1/2 cup miniature marshmallows
• 1 1/2 teaspoons vanilla

Topping:

• 1/4 cup honey roasted peanuts coarsely chopped

Instructions

• Preheat your oven to 350°F. and prepare a 9×13 baking pan by spraying generously with non-stick spray and set aside.
• In the bowl of a stand mixer equipped with a paddle attachment, cream the peanut butter and both sugars until light and fluffy.
  
• Scrape the sides and bottom of the bowl and ad in the milk, vanilla, eggs, and oil, and mix until well combined.
• Sift in the flour, baking soda, baking powder, and salt and mix until there are no dry spots remaining.
• Pour the cake batter into the prepared pan and bake for 25-30 minutes or until a toothpick inserted in the center of the cake comes out clean. Remove from the oven and frost immediately.
  

MARSHMALLOW FROSTING:

• About 5 minutes before the cake is scheduled to be removed from the oven start to make the frosting.
• In a medium saucepan, combine the sugar, evaporated milk and butter and heat over medium-high, stirring continuously.
• When sugar is dissolved, add the peanut butter, marshmallows and vanilla. Stir until smooth and fully incorporated over very low heat.
• Pour warm frosting mixture over the hot Peanut Butter Cake and spread around to cover fully. Sprinkle with honey roasted peanuts immediately while frosting is still tacky.
  
• Allow to cool completely before serving.
• If you’ve tried this recipe, come back and let us know how it was in the comments or ratings.

Nutrition

Calories: 435 kcal, Carbohydrates: 59 g, Protein: 11 g, Fat: 19 g, Saturated Fat: 6 g, Polyunsaturated Fat: 4 g, Monounsaturated Fat: 7 g, Trans Fat: 1 g, Cholesterol: 26 mg, Sodium: 291 mg, Potassium: 317 mg, Fiber: 2 g, Sugar: 39 g, Vitamin A: 95 IU, Vitamin C: 1 mg, Calcium: 77 mg, Iron: 2 mg

Author: Chef Jessica Anne

Calories: 435

Course: Dessert

Cuisine: American

Keyword: marshmallow frosting, peanut butter cake, sheet cake

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