Marshmallow Moon Pie Cake (Updated)
Marshmallow Moon Pie Cake (Updated) – Inspired by Ben and Jerry’s ice cream flavor by Jimmy Fallon, my Marshmallow Moon Pie Cake will make you think you’re biting into the classic junk food treat, a Moon Pie.
Old Marshmallow Moon Cake
Nearly two years ago I created my Marshmallow Moon Cake, inspired by Ben and Jerry’s Moon Pie ice cream flavor they co-created with Jimmy Fallon. Similar to my Tonight Show Cake, I took all the flavors of the ice cream and used them to inspire each element of the cake.
In this cake you have vanilla cake layers, marshmallow filling, a graham cracker crumble and chocolate ganache. Sound familiar? It’s basically a vanilla s’mores cake!
Milk-Bar Style
In my first edition of my Marshmallow Moon Pie cake, I built the cake Milk-Bar style. I love how Christina Tosi shows off her cake layers with this technique. You can look back at my original post for instructions on how to build a cake like this – just click HERE.
New Marshmallow Moon Pie Cake
It’s been a while since I made this cake and I was eager to revisit it. It’s just so good! As I was thinking about the cake and all the elements, I felt like it was really missing a buttercream – because it was! In my first edition, there’s no buttercream with this cake. (Say it ain’t so!). I also wanted to switch things up and stack and decorate it like one of my usual cakes.
Since this is basically a vanilla s’mores cake, and I’ve already done a chocolate s’mores cake (Ultimate S’mores Cake), I decided to create a graham cracker buttercream instead of a chocolate buttercream for my Marshmallow Moon Pie cake.
Oh friends! This graham cracker frosting is a serious game changer! With a hint of cinnamon and lots of graham cracker, the flavor is just so good. I love how it brings the whole cake together.
And because this Marshmallow Moon Pie cake is so tall, I like to cut two layers down and serve the top half first and then serve the bottom two layers. You’ll get about 16 slices of cake this way.
Helpful Tips
- Be careful not to over bake the Marshmallow Moon Pie cake layers. Remember, when you insert a toothpick in the center of the cake, a few moist crumbs should come out. The cake continues to bake for about 5 minutes while it’s cooling.
- Everything can be made ahead of time and stored in the freezer or fridge. Bring the fillings and frosting back to room temperature before assembling the cake. Cake layers should be chilled, but not frozen, when you assemble.
- Make sure to apply a crumb coat – a thin layer of frosting that you’ll freeze on the cake for 10 to 15 minutes to lock in the crumbs. This ensures you don’t get any crumbs in your final coat of frosting.
- If you notice that you have to push really hard on your frosting to spread it around the cake, it’s the wrong consistency. You shouldn’t ever have to apply too much pressure to spread the frosting. If you have stiff frosting, repeat it in the mixer and add a little extra heavy whipping cream.
Marshmallow Moon Pie Cake
Ingredients
FOR THE CAKE
- 1 cup (226 g) unsalted butter room temperature
- 1/3 cup (72.6 g) canola oil
- 1 teaspoon (5.6 g) salt
- 2 cups (400 g) granulated sugar
- 8 large egg whites room temperature
- 3 cups plus 4 tablespoons (373.75 g) cake flour
- 2 teaspoon (8 g) baking powder
- 1 cup (240 g) sour cream room temperature
- 1 tablespoon (4.2 g) vanilla bean paste
FOR THE TOASTED GRAHAM CRACKER CRUMBLE
- 3 tablespoons (42.4 g) unsalted butter
- 2 tablespoons (27.5 g) brown sugar
- 9 whole graham crackers
FOR THE TOASTED MARSHMALLOW FILLING
- 24 large white marshmallows
- 2 cups (250 g) powdered sugar measured and then sifted
- 1 cup 2 sticks (226 g) unsalted butter, room temperature
- 1 teaspoon (4.3 g) pure vanilla extract
- 1 jar about 200 g marshmallow fluff
FOR THE CHOCOLATE GANACHE
- 1 cup (150 g) dark chocolate chips
- 1/2 cup (115.5 g) heavy whipping cream
FOR THE GRAHAM CRACKER FROSTING
- 2 cups (452 g) unsalted butter slightly cold
- 5 1/2 cups (687.5 g) powdered sugar measured and then sifted
- 1/2 cup (60 g) about 7 full graham crackers, ground into sand-like consistency
- 1 teaspoon (2.6 g) ground cinnamon
- 1/4 cup (57.75 g) heavy whipping cream
- 1 teaspoon (4.2 g) vanilla extract
- Pinch of salt
- **This buttercream recipe makes enough to fill and cover your cake. If you want to add additional piping, you’ll want to make an extra 1/2 batch.
Instructions
FOR THE CAKE
- Preheat the oven to 350 degrees F. Prepare four 6-inch (or three 8-inch) round cake pans by spraying the bottom and sides with non-stick spray, lining the bottom of each pan with parchment paper and spraying again. Set aside.
- In a medium size bowl, whisk together the cake flour, salt and baking powder. Set aside.
- In the bowl of a stand mixer, fitted with the paddle attachment, beat the butter, oil, and sugar on high until fluffy and smooth, about 5 minutes.
- Add the egg whites, one at a time to the bowl and beat on medium until well incorporated. Make sure to scrape down the sides of the bowl between additions.
- Turn the mixer on low and add 1/3rd of the flour mixture to the butter mixture and mix for 20 seconds. Then add half of the sour cream and blend well. Repeat alternately adding the flour, sour cream and remaining flour. Mix until incorporated.
- Add the vanilla bean paste and beat on low until incorporated, only about 10 to 20 seconds. Scrape down the sides of the bowl and mix on low for another 10 to 20 seconds.
- Pour the cake batter evenly between the four 6-inch pans or three 8-inch pans and bake about 23-25 minutes or until a toothpick inserted into the middle of the cake comes out clean or with just a few crumbs. Make sure not to over bake.
- Remove cake from the oven and let cool in the pan for 10 minutes before inverting onto cooling racks.
- Once cooled, you can level the cake layers if needed and then wrap well in plastic wrap and freeze for at least an hour before you assemble the cake. Can be stored in the freezer wrapped once in plastic wrap for about a week. If you want to store the cake layers longer, wrap twice with plastic wrap and then again with foil.
FOR THE TOASTED GRAHAM CRACKER PIECES
- Preheat the oven to 350 degrees. Line a baking sheet with parchment paper. Set aside.
- Place the crackers in a gallon sized zip-lock bag and crush them into pieces using a rolling pin. Set aside.
- Melt the butter and mix in the brown sugar. Stir until combined.
- Pour the butter and brown sugar mixture over the graham cracker pieces in the zip-lock bag and shake to coat.
- Bake the graham cracker pieces for 10 minutes. Let cool completely before using in the cake. Store in an airtight container until ready to use.
FOR THE TOASTED MARSHMALLOW FILLING
- Line a baking sheet with parchment paper and spray with nonstick cooking spray. Place the marshmallows on the cookie sheet. Place on the middle rack of the oven, and broil the marshmallows until golden brown on top, about 30-60 seconds. Keep your eye on them!
- Remove the pan from the oven and gently turn the marshmallows over and broil them again until they are golden brown on the other side.
- In the bowl of a stand mixer fitted with the paddle attachment, combine the butter and powdered sugar and beat on low until blended. Add the vanilla and mix on medium speed for about three minutes
- With the mixer on low speed, add the marshmallow cream and (cooled) toasted marshmallows, and mix for about one minute.
FOR THE CHOCOLATE GANACHE
- In a microwave safe container, heat the cream for about 30 to 60 seconds. Pour the cream over the chocolate chips and let sit for 5 minutes. Stir the cream and chocolate until smooth and silky.
FOR THE GRAHAM CRACKER FROSTING
- In a stand mixer fitted with the paddle attachment, beat the butter on medium high speed until light and fluffy, about 2 minutes.
- With the mixer on low speed, gradually add the powdered sugar, followed by the graham cracker. Make sure to scrape down the sides and bottom of the bowl.
- Add the cinnamon, vanilla, salt and cream.
- Turn the mixer to medium-high speed and beat the frosting for about 5 minutes.
- Before frosting your cake, make sure to mix the frosting by hand to push out the air pockets.
ASSEMBLY
- Place the first cake layer, top-side up, on a cake board.
- Pipe a rim of the graham cracker frosting around the edge of the cake.
- Evenly spread about 1/2 cup of the marshmallow filling over the cake layer.
- Cover with about 1/4 cup graham cracker crumble and pat into place.
- Drizzle chocolate ganache over the graham crackers.
- Repeat these steps until you get to the final cake layer, which you'll place top-side down on the last layer of filling.
- Apply a thin layer of frosting around the entire cake and then freeze the cake for 10 to 15 minutes. This is the crumb coat. The crumb coat is done to lock in the crumbs of the cake so you don't get them in your final coat of frosting.
- After the crumb coat is set, finish frosting your cake.
- For the piping, I combined some of my leftover marshmallow filling with the leftover frosting.
Hi Courtney – can you direct me to a reference, or tell me here, how to break down this cake into steps/days in advance? Obviously I know I can make the cake layers ahead of time, but what about the other elements listed?
You can make the graham cracker crumble ahead of time and store in an airtight container. Same for the frosting and marshmallow filling. The ganache I would make same day of assembly.
AMAZING cake! Lots of steps, but nothing tough. The frosting and the marshmallow filling is out of this world good. Just wondering, is it possible to save the marshmallow filling? I had a lot left over, but not sure for how long (or if) it can be stored.
It will only be good for a little and then it wills start to seperate.
Hi Courtney!! First, I have made a few of your cakes and they are always delicious.
For this one, my cake layers came out surprisingly flat. I am wondering if it was because I actually weighed the ingredients using a scale and not using cup measurements. The 3 cups of cake flour I didn’t use a cup measurement but instead my kitchen scale to mass out 374 g of cake flour. Could this be what went wrong?
Thanks for your help. 🙂
-Kerry
It could be that you overmxied or some of your ingredients were old!
I’m trying to decide between this cake and your milk bar version. I love the look of the milk bar version, but love the addition of the buttercream in this one. Do you think it would work to stack this cake “milk bar style” but add the buttercream between the cake layers instead of on the outside? If so, what order would you suggest adding the fillings?
Thanks <3
Why not! Do the buttercream first then marshmallow.
Should I store the graham cracker crumbs in the fridge once toasted or on the counter if I make them ahead of time?
Will the cake layers get dry if I make the day ahead of refrigerate?
Graham crackers sealed on the counter is fine. And then the cake should be in the freezer! Fridge will dry out.
If I make the marshmallow filling ahead of time would it store on the counter or in the fridge until I’m ready to assemble the cake?
yes!
Oh my gosh!!!!! This cake!!!! By far the best cake I’ve ever had or made in my life!!!!!!! Your my hero! I am beyond excited to show this one off! Thank you.
Thank you so much!
I love every cake of yours I’ve tried. I’m going to make a cake for a construction-themed birthday party & like the rustic look of your previous moon cake that I’ll just add construction trucks to, but I love that this has the buttercream. Can I add layers of buttercream to the milk bar style previous version? Thanks so much!
Yes for sure!