S’mores Cake With Toasted Marshmallow Buttercream

smores cake recipe by sugar and sparrow

There’s something about me you’ve got to know: I really really love s’mores. I had my first one as a kid sitting around a crackling campfire under the stars and have been hooked ever since. There’s something about a perfectly toasted marshmallow, melty milk chocolate, and crunchy graham crackers that just gets me all shook up. Since discovering this fun little fact about me, my mother-in-law keeps her pantry stocked year-round with all the s’mores essentials to make sure I can have them any time I come over. No matter what time of year, you’ll find stacks of Hershey’s bars, jet puffed marshmallows, and honey graham crackers tucked away in my very own corner of her pantry and it makes me feel very known and loved. It was just a given that I would turn these flavors into a cake, and it’s one of the very first recipes I sought to master.

toasted marshmallow smores cake by sugar and sparrow

The s’mores cake I’ve created goes like this: layers of graham cracker cake filled with toasted(!) marshmallow buttercream and milk chocolate ganache, topped with vanilla buttercream, a milk chocolate drip, and toasted marshmallow meringue flourishes. Phew. Sounds like heaven right? If you love s’mores, it really is. It’s been one of my most requested flavors to date, and based on the reviews I’ve heard I wouldn’t hesitate to call it a true crowd pleaser.

toasted marshmallow meringue recipe by sugar and sparrow

toasted smores cake recipe by sugar and sparrow

There are a whole lot of yummy flavors going on in this cake, but I think the real kicker comes from the toasted marshmallow buttercream. It involves mixing in some Marshmallow Fluff and jet puffed marshmallows that have been toasted in the oven, so you get a bit of that smokey, marshmallowy taste that will remind you of a campfire. Paired with the graham cracker cake and milk chocolate ganache, I’d say it’s the closest match to a real s’mores you’re going to find in cake form.

To make sure you get the purest s’mores taste with each bite of this cake, I layer the toasted marshmallow buttercream with chocolate ganache as a double filling. That way you get a little bit of everything all at once, just like the real deal. And it makes for really pretty slices too.

graham cracker cake recipe by sugar and sparrow

toasted marshmallow buttercream recipe by sugar and sparrow

I’m a big fan of highlighting the flavors of the cake by decorating with crushed graham crackers, a milk chocolate ganache drip, and toasted marshmallow meringue flourishes. I use Wilton tips 1M and 4B to pipe the meringue before toasting, and I love how this recipe holds its shape. Years ago I tried this same technique with marshmallow fluff and it did not hold its shape for more than ten seconds, then afterwards melted into a puddle of white goo. It was a heartbreaking situation, but it’s what led me to discover my absolute favorite marshmallow meringue recipe and I haven’t ever looked back. It’s super easy to make, pipes like a dream, and looks gorgeous when it’s toasted.

whipped meringue recipe for piping

toasted meringue recipe by sugar and sparrow

If you’re on the fence about getting a good culinary torch, let me tell you, it makes all the difference for toasted desserts. I’ve been using this micro butane culinary torch for the past year and it’s worked wonders, plus it’s under $20 which is a complete steal. Toasting the meringue flourishes is the perfect final touch for this recipe, and it’s absolutely my favorite part.

smores cake recipe by sugar and sparrow
5 from 6 votes
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S'mores Cake Recipe

Three layers of graham cracker cake filled with toasted marshmallow buttercream and rich milk chocolate ganache, topped with vanilla buttercream and garnished with toasted marshmallow meringue flourishes. 

Servings 15 slices

Ingredients

Graham Cracker Cake

  • 1 1/2 cups (155g) graham crackers, ground into crumbs
  • 3 3/4 cups (398g) cake flour, sifted before measuring
  • 1 Tbsp baking powder
  • 3/4 tsp baking soda
  • 1 1/2 tsp salt
  • 1 1/8 cups (254g) unsalted butter, room temperature
  • 2 cups (410g) granulated sugar
  • 5 large eggs, room temperature
  • 1 1/2 Tbsp vanilla extract
  • 1/2 cup (112g) sour cream, room temperature
  • 1 1/2 cup (360ml) whole milk, room temperature

Toasted Marshmallow Buttercream

  • 8 large marshmallows
  • 1/2 cup (113g) unsalted butter, room temperature
  • 1/2 cup (60g) powdered sugar
  • 1/2 tsp vanilla extract
  • 3.5 oz (half a small jar) Marshmallow Fluff
  • 1/4 tsp salt

Milk Chocolate Ganache

  • 1 cup (183g) milk chocolate chips
  • 1 cup (240ml) heavy whipping cream

Vanilla Buttercream

  • 2 cups (452g) unsalted butter, room temperature
  • 7 cups (840g) powdered sugar
  • 4 Tbsp (59ml) whole milk, room temperature
  • 4 tsp vanilla extract
  • 1/4 tsp salt

Marshmallow Meringue Topping

  • 3 large egg whites, room temperature
  • 3/4 cup (150g) granulated sugar
  • 1/4 tsp cream of tartar
  • 1 tsp vanilla extract

Instructions

Make The Graham Cracker Cake

  1. Preheat the oven to 350˚F and prepare three 6-inch cake pans by spraying the sides with cooking spray and fitting a parchment or wax paper circle to the bottom of each pan. 

  2. Grind the graham crackers into a crumbs by either using a food processor or placing them into a large ziplock back and crushing them with a rolling pin. Place the graham cracker crumbs into a medium sized bowl and add the sifted cake flour, baking powder, baking soda, and salt. Whisk to combine and set aside. 

  3. In the bowl of a stand mixer with the paddle attachment, cream butter for one minute on high. Scrape down the bowl and paddle and add the sugar. Cream together on high for two minutes, scraping down bowl and paddle once in between. Turn mixer to low and add the eggs, one at a time, scraping down bowl and paddle as necessary. Once all eggs are added, turn the mixer to high and beat for three minutes. 

  4. Add vanilla and sour cream and continue mixing for one minute. Turn the mixer to low and add all of the dry ingredients at once until just combined, then add the milk all at once. Scrape down the bowl and paddle once more and mix on low for about 30 seconds. Do not overmix.

    Pour batter into prepared pans (about ⅔ full). 

  5. Bake for 35-45 minutes or until a toothpick inserted into the center comes out clean. Cool the cakes for five minutes before releasing from the pan and continuing to cool on a baking sheet or wire rack.

Make The Milk Chocolate Ganache

  1. Place chocolate chips in a heatproof bowl. In a saucepan over medium-high heat, whisk heavy whipping cream constantly until you start to see the beginnings of a boil. Just before it begins to form a rolling boil, remove the cream from the heat and pour over chocolate chips. Let the mixture sit for about 30 seconds, then whisk it all together until smooth and uniform in consistency. Cool the ganache on the counter until it reaches room temperature before using in/on the cake.  

Make The Toasted Marshmallow Buttercream

  1. Line a baking sheet with aluminum foil and lightly spray the surface of the foil with cooking spray. Place your marshmallows on the foil and set in the center rack of the oven. Broil the marshmallows on high until they start to brown on top (watch them closely!), then flip them over so they can brown on the bottom as well. When both sides are toasted, take them out of the oven to cool.

  2. In a stand mixer with the paddle attachment, whip the butter on medium until creamy and light in color, about 5 minutes. Add the powdered sugar and continue mixing on low for another 2 minutes, scraping down the bowl and paddle afterwards. Add the vanilla and beat on medium for 3 minutes, then add the marshmallow fluff, roasted marshmallows, and salt. Continue mixing on medium for another minute.

Make The Vanilla Buttercream

  1. In a stand mixer with the paddle attachment, beat butter on high for until it’s fluffy and almost white in color, about 7 minutes, scraping down the bowl and paddle a few times during the process. Add the powdered sugar a few cups at a time and mix on medium until incorporated. Scrape down the bowl and paddle before each addition. Turn the mixer to low and add the vanilla extract, milk, and salt. Beat on medium for another minute until well incorporated, scraping down the bowl and paddle as needed.

Make The Marshmallow Meringue

  1. Whisk the egg whites, sugar, and cream of tartar together in a small heatproof bowl. Set the bowl over a saucepan filled with an inch or two of simmering water, making sure the bottom of the bowl doesn’t touch the water (or else it will cook your eggs!). Whisk the mixture constantly until the sugar has dissolved, about 4 minutes. 

  2. Once the sugar has dissolved, pour the mixture into the bowl of your stand mixer fitted with the whisk attachment. Add the vanilla and whisk the mixture on high for 6 full minutes, until stiff peaks form. You should be able to dip the whisk into the meringue and it forms a peak that maintains its shape when turned right side up and upside down. 

Assembly

  1. Torte each layer of graham cracker cake to desired height. Pipe a circle of vanilla buttercream around the edge of the first layer to act as a buttercream dam. Fill the center of the circle with half chocolate ganache (room temperature or colder), and half toasted marshmallow buttercream. Place the next layer of graham cracker cake on top and repeat the filling process before placing the third layer on top.

  2. Crumb coat the cake with vanilla buttercream and place it into the refrigerator for 15 minutes before topping with a final coat of vanilla buttercream. Garnish the cake with a chocolate ganache drip, graham cracker crumbs, and marshmallow meringue piping that’s been toasted with a culinary torch. Or decorate however your heart desires. 

Recipe Notes

Make ahead tips: the cake can be made ahead and stored at room temperature (wrapped in plastic wrap) for up to two days before frosting. Alternatively, you can wrap it in plastic wrap and store in the freezer for up to two months. 

The buttercreams can be made ahead of time and stored in airtight containers in the refrigerator for up to two weeks. When you're ready to use them, bring them to room temperature and re-whip with the stand mixer if needed. 

The ganache can be made ahead and stored in an airtight container in the refrigerator for up to two weeks. When you're ready to use it, bring back to room temperature. You can microwave it in small (10-15 second) increments to get it back to drip consistency.

The marshmallow meringue cannot be made ahead and must be used/toasted as soon as you make it. 

Did you make this recipe? I’d love to hear what you think! Let me know in the comments and tag me on Instagram to show me photos!

29 Comments


  1. LOOKS AMAZING! Making tomorrow. Quick question- what did you mean by “cereal milk” in the graham cake bit?

    Thanks!

    • I can’t wait for you to try this recipe, Jenn! Let me know how it goes! And good catch on that typo. I meant “whole milk” in the graham cracker cake instructions 🙂

    • Hi Victoria! You can certainly make this cake in an 8 inch pan. If you want a two layer 8 inch cake, leave the recipe as is. If you want a triple layer 8 inch cake, I’d double the cake portion of the recipe just to be safe.

      • Thank you! Can you tell me what the layer height is on the 6″ you use?

      • Hi! I have a question about doing a 3 later 8” cake – should only the cake be doubled, or should the vanilla buttercream be doubled as well? Thanks!

        • Hi Carla! I would just double the cake. All of the other components will be enough to cover an 8 inch cake with three layers 🙂

  2. Can you substitute almond milk? Also, can I skip powdered sugar and use regular?

    • Hi Allie! Although I have never tried it myself (so not sure how it will taste), you can substitute almond milk in the cake recipe and the buttercream recipe. As far as the powdered sugar goes, it cannot be substituted with regular granulated sugar. The fine-ness of the powdered sugar is necessary to turn that butter into buttercream 🙂


  3. Hi Whitney, this cake looks and sounds amazing! I’m definitely going to be trying it.
    Just wondering, how far in advance can you decorate with the meringue on top before it would start to run down the side of the cake?
    Thank you

    • Hi Agnes! Can’t wait for you to try this cake! For the meringue topping, you have to whip it up right before you want to pipe with it. I found that storing it in the fridge and trying to pipe with it at a later date doesn’t work. After you make the meringue, you can pipe it onto the cake and the consistency will be stiff enough that it won’t run down the sides at all. I usually toast the meringue right after piping it. It will keep for a few days in the refrigerator after you toast it, beyond a few days it will start to weep. So my recommendation would be to make the cake the day before you want to serve it if you want to make it ahead of time.

  4. kemala hayati

    Hi i wanna try this recipe, but would u please convert this to gram?
    it would be helpful for me and other international reader who rarely use cups thanks

    note: if possible please add gram conversion to all of ur recipe✌

    • Hi Kemala! I am working on converting all the recipes to grams this week (just bought my first kitchen scale!). I’ll make an announcement once they’ve all been converted. Make sure you’re signed up for my email list so you’ll be one of the first to know!

  5. Sonal Chaddha


    Just wanted to let you know that I made this cake exactly as it was in the picture. It turned out perfectly and I finally get what you meant by making the meringue just before I ice. I made mine a few hours prior and they did not hold as well but still I managed to make them look close enough.

    Will Tag you in my pictures. This will forever be my go to S’mores cake recipe.
    Thank you so much!!

    • Hi Sonal! I’m so happy to hear you loved the s’mores cake! And yes – the meringue starts to lose it’s shape over the course of a few hours. It’s best to make it right before you pipe it, because after it’s piped it won’t lose its shape! I’m glad it still piped well and I can’t wait to see your cake!

  6. Halima Yahya Khan


    Hi. This cake looks absolutely yummy, in fact all your cake does. I will be trying them soon. Lots of love and best wishes to you


  7. Hi! I made this cake using the same recipe but for 6” pans. I had leftover batter so I made ten cupcakes! Used the toasted marshmallow as filling for the cupcake. Dipped them in the ganache and piped vanilla buttercream on top with a dollop of the marshmallow merengue and then torched it. Both came out great! Thank you!!!!

    • Oh my goodness Melanie! The cupcake version sounds amazing! I’m gonna have to try that myself 🙂 So happy you loved the recipe!

  8. What would be your thoughts on frosting the outside of a cake with the Toasted Marshmallow Buttercream? Would it be stable enough and be able to be used to create smooth sides? Thanks!

    • Hi Jennifer! You could totally use the toasted marshmallow buttercream on the outside of the cake. I’m sure you could get a smooth buttercream finish with a little work (just because of the toasted marshmallow chunks). I’d recommend adding a little milk to thin it out to frosting consistency but I think it would work great!

  9. Hi! Can I use buttermilk instead of whole milk for the cake batter? If yes, would it be the same amount?


  10. Love this recipe! That marshmallow buttercream is FANTASTIC!! Out of curiosity- why is this vanilla buttercream different than your other? Why more powdered sugar?

    • Hi Kayla! Thanks so much – so happy you’re loving the marshmallow buttercream recipe! And there’s no difference between this vanilla buttercream and my other one, it’s just a double batch 🙂

  11. Donna Walden

    This cake is so cute! Making it for my grandson’s birthday. Can you explain how you applied the graham cracker crumbs to outside of cake?

    • This is going to make such a great birthday cake for your grandson, Donna! For applying the crushed graham crackers, after frosting the cake I cupped the graham cracker crumbs in my hand and gently pressed them to the sides of the cake. Here’s a video showing the technique, but with cookie crumbs: https://www.youtube.com/watch?v=o0ueDZbC2-U&t=1s

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