Chocolate Peanut Butter Marshmallow Cake - Dark chocolate cake layer, with a creamy and smooth peanut butter frosting, topped with a homemade marshmallow fluff.
Small in size, but mighty in flavor, this Chocolate Peanut Butter Marshmallow Snack Cake is the ultimate snack cake. While there are three elements to this small cake, it will serve a small crowd, but can be easily doubled for a much larger crowd.
For other chocolate related desserts, here are some below!
- Chocolate Cake With Peanut Butter Frosting
- Delectable And Easy Oreo Peanut Butter Cake
- Easy One Bowl Peanut Butter Oreo Bars
Jump to:
Why make this Chocolate Peanut Butter Marshmallow Cake?
- Moist chocolate cake - Who doesn't love a moist high quality chocolate cake? This cake is incredibly moist, and has dark chocolate incorporated into it!
- Easy to make - This cake is easy to make and it's so hard to mess up. All you have to do is mix all the wet ingredients into the sifted dry ingredients and you're ready to go!
- Peanut Butter Buttercream - This frosting is made from creamy peanut butter which makes the frosting extra creamy. My favorite peanut butter brand is Skippy.
- Marshmallow fluff - wether you want to make your own, or just buy a small jar, this part adds the best sweetness and fluffiness the cake needs!
- Small in size - this cake is made in an 9x9 or 8x8, for those small cake occasional needs
Ingredients List
- Dark Cocoa Powder - I get mine from amazon. You can find it here:
- Baking powder & baking soda - These ingredients give the cake its rise. I get a new container of each every month to make sure they are fresh. This guarantees I get a great rise on all of my cakes.
- Eggs - I always make sure they are at room temperature when I start to bake by pulling them out of the fridge a couple hours before I need them.
- Hot water - This helps the chocolate cocoa powder flavor blossom.
- Heavy Cream - You will want this for your buttercream! Without it, it makes the buttercream very dry!
- Smooth peanut butter - I use smooth and creamy Skippy peanut butter.
- Corn syrup - this is for the marshmallow fluff, but no worries if you want to just buy your own jar instead of making it!
Step By Step - Chocolate Peanut Butter Marshmallow Cake
Next, I have made a detailed list on to make this cake. I use my kitchen aid which I got from here. You can also use two bowls and whisk!
Step 1: Prep. Preheat your oven to 325 degrees F. Spray an 8×8 square inch cake pan with cooking spray, line with parchment paper, and spray again. Set aside.
Step 2: Combine all the dry. In a stand sized mixer fitted with the paddle attachment, combine the flour, sugar, cocoa powder, baking soda, baking powder, and salt. Mix on low until evenly combined.
Step 3: Whisk all the wet. In a small bowl, whisk the eggs, buttermilk, hot water, vanilla extract, and vegetable oil until evenly combined.
Step 4: Add the liquid to the dry. With the mixer on the lowest speed, pour the liquid ingredients into the dry ingredients and mix just until combined. There should be no flour streaks. With a rubber spatula, scrape the bottom of the bowl to make sure the batter is evenly combined.
Step 5: Pour and bake. Add the the batter to the prepped pan, and carefully smooth the batter with a small offset spatula and bake until a toothpick comes out clean, or with only a few crumbs on it, about 35-40 minutes. Depending on your oven.
Step 8: Cool. Let the cake cool for 10 minutes, and then transfer to the fridge or freezer to completely cool while you prep the frosting and the marshmallow.
Expert Baking Tips
- Use high quality cake pans. This helps prevent your cake layers from browning on the side. I love USA Pans
- I say this a lot, but there is a reason. USE ROOM TEMP ingredients! That is a must! Make sure all of your ingredients are at the same temp!
- To get a creamy and smooth buttercream, When you finish making the buttercream, add some cream to your buttercream and beat by hand with a rubber spatula to get all the air bubbles out.
- I love using an offset spatula to help spread the buttercream onto the sides of the cake.
Frequently Asked Questions - Chocolate Peanut Butter Marshmallow Cake
Can I use a 9×9 instead of 8×8?
You sure can! No need to adjust too much, check your cake a few minutes before the recipe calls.
Can I double this recipe?
Yes! This recipe can easily be doubled and made into a 9×13! Just make sure to also double the frosting!
Can I turn these into cupcakes?
Yes you can! It will make 18 cupcakes. Bake for 16-18 minutes until baked completely. You can use this muffin tin and these cupcake liners. To add the frosting and marshmallow, in a piping bag, add half of the peanut butter frosting to one side, and the marshmallow fluff to other.
Storing And Freezing
Store the Chocolate Peanut Butter Marshmallow Snack Cake
in an airtight container at room temperature or in the fridge. I like to cover mine in plastic wrap and store up to 5 days (if it even lasts that long)
Freezing
Freeze it whole or cut up! You can freeze it full frosted and I suggest wrapping the cake in plastic wrap before freezing.
How to serve: once the cake is frosted, you can cut it up into 9, 12 or 16 pieces. Serve at room temperature! My husband likes to eat it in a bowl of milk!
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Recipe
Chocolate Peanut Butter Marshmallow Snack Cake
Ingredients
For the chocolate cake
- 2 eggs room temperature
- ½ cup buttermilk room temperature
- ½ cup hot water
- ¼ cup vegetable oil
- 1 cups all-purpose flour
- ¾ cups granulated sugar
- ½ cup dark cocoa powder
- 1 teaspoons baking soda
- 1 teaspoon baking powder
- ¾ teaspoon salt
- 2 teaspoons pure vanilla extract
For the peanut butter frosting
- 2 ½ cups powdered sugar measured and then sifted
- ½ cups unsalted butter room temperature
- ½ cup creamy peanut butter I use Skippy
- 1 Tablespoon pure vanilla extract
- 2-3 tablespoons
- heavy whipping cream
- Pinch of salt
For the marshmallow fluff
- Note: you can just buy a 7 ounce jar of marshmallow fluff if you don't want to make your own
- 2 egg whites room temperature
- Pinch
- 3 tablespoons granulated sugar
- ½ cup light karo syrup
- 2 tablespoons 29.6 g water
- 1 teaspoon vanilla extract
Instructions
For cake
- Preheat your oven to 325 degrees F. Spray an 8×8 square inch cake pan with cooking spray, line with parchment paper, and spray again. Set aside.
- In a stand sized mixer fitted with the paddle attachment, combine the flour, sugar, cocoa powder, baking soda, baking powder, and salt. Mix on low until evenly combined.
- In a small bowl, whisk the eggs, buttermilk, hot water, vanilla extract, and vegetable oil until evenly combined.
- With the mixer on the lowest speed, pour the liquid ingredients into the dry ingredients and mix just until combined. There should be no flour streaks. With a rubber spatula, scrape the bottom of the bowl to make sure the batter is evenly combined.
- Add the the batter to the prepped pan, and carefully smooth the batter with a small offset spatula and bake until a toothpick comes out clean, or with only a few crumbs on it, about 35-40 minutes. Depending on your oven.
- After they are out of the oven, I let mine cool for 15 minutes. Then I transfer the cake onto a wire rack to finish cooling in the fridge or freezer to help speed up the process. (20 minutes in the freezer, 30 minutes in the fridge)
- While the cake is cooling, make the frosting.
For the peanut butter buttercream
- In the bowl of electric mixer fitted with the paddle attachment, combine the butter and peanut butter. Beat on medium-high speed until smooth, about 2 minutes.
- With the mixer on the lowest speed, add the powdered sugar, vanilla, salt, and cream to the bowl. Once mixed, beat on high for 3 minutes, scrape down the bowl and beat for 1 more minute. It should look light and fluffy.
- Use a wooden spoon to mix frosting one last time to get rid of air bubbles.
For the marshmallow fluff
- In the bowl of a standing mixer, use a whisk to combine the eggs and salt until frothy, once frothy, keep the mixer on the lowest speed to keep the stabilized.
- While the egg whites are whipping, in a small sauce pan, combine the sugar, corn syrup, water and vanilla over medium heat. You want the sugar to dissolved, so roughly 3-5 minutes.
- Once the sugar has melted, turn the the mixer on medium-high speed, and slowly start to pour the hot sugar mixture on the mixing bowl's inside rim, letting it run down the side of the bowl. Make sure to pour VERY slowly. If you do this correctly, you will temper your eggs, and not scramble them. This will take about 2 minutes.
- Once all of the sugar has be added, turn the mixer up to high speed, and beat for about 5 minutes or until very stiff and shiny. (This does not hold well, so make sure to to use day of.
Assembly
- Once the cake has cooled (or chilled) and is no longer warm, using the peanut butter frosting, frost the top of the cake. To achieve this, I use a small offset spatula and a large cookie scoop to scoop 9 balls across the top. This help the frosting spread evenly.
- Next add the marshmallow fluff and evenly spread, you might not use all of the marshmallow fluff, you can store the left over in a plastic bag and freeze it for up to 3 months,
- Cut into 9-12 slices and serve!
Kara says
I made this right when you posted this recipe. I am at awe! The chocolate and PB is always a good choice, but when you add the marshmallow, it takes the entire cake to a whole new level. I liked the size of it, too! Will be saving and making this again.
Anonymous says
Thank you for sharing this recipe