Is this the ultimate homemade s’mores cake? I’ll let you be the judge! This s’mores cake is a decadent combination of moist chocolate cake, toasted marshmallow buttercream, graham cracker crunchies, and chocolate ganache. If you’re a s’mores lover, this layer cake is definitely for you!
When it comes to summer evenings, one of the best things is a warm, gooey s’more. The graham crackers, the chocolate, the toasty marshmallows… what’s not to love? In this s’mores cake, all those components come together with my best moist chocolate cake to make the most amazing cake inspired by the tasty classic campfire treat.
The final s’mores cake is truly a thing to behold. It’s beautiful on the outside and FULL of flavor on the inside. The recipe requires a few steps, but each layer is really quite simple to put together, and it comes together easily. It’s fun to make and will certainly impress a crowd. This is the perfect cake for summer, and I hope you enjoy it!
What You Can Expect From This S’mores Cake
- Moist chocolate cake. My original cake recipe (linked above) is an all-time favorite and has dozens of amazing reviews. It’s moisture and rich crumb make it perfect for layer cakes. I use the same base recipe for my s’mores cupcakes.
- Toasted marshmallow frosting. You can’t make a s’more without a toasted marshmallow! The frosting uses whole marshmallows toasted in the oven, cooled, and then broken apart to be added to the marshmallow fluff frosting. So good!
- Graham cracker crunchies. Graham cracker crumbs are combined with some sugar and melted butter and then toasted to create little crunchies.
- Chocolate ganache. Obviously, some form of melty chocolate needed to be included in this s’mores cake recipe. Homemade chocolate ganache is about as close as you get to the melted Hershey bar in the real thing!
Ingredient Notes
Let’s take a look at the key ingredients in this s’mores layer cake. The full recipe with exact measurements for each ingredient can be found in the recipe card at the end of the post.
- Flour – Make sure to measure the flour correctly using a kitchen scale, or the spoon and level method. Too much flour makes the cake dry.
- Cocoa powder – I recommend natural unsweetened cocoa powder in this recipe.
- Vegetable oil – For an ultra-moist, tender chocolate cake. Choose a neutral-flavored oil, like canola or vegetable oil.
- Hot water – Hot water “blooms” the cocoa powder and enhances the chocolate flavor in the cake.
- Graham crackers – I crushed up about 6 full graham cracker sheets to make 3/4 cup of crumbs. You’ll combine the crumbs with melted butter and sugar, similar the mixture in a graham cracker crust, to make the crunchies between the cake layers.
- Marshmallow Fluff – For the marshmallow frosting. I used nearly two full 7-ounce jars.
- Mini marshmallows – The marshmallows are toasted in the oven and added to the marshmallow frosting. They add some authentic toasted marshmallow flavor and a little bit of chewiness to the frosting.
- Chocolate chips – To melt with heavy cream for the chocolate ganache. Chocolate chips will work here, but for an extra-smooth ganache, use baking bars or similar.
- Frosting – I use vanilla buttercream to pipe a stable barrier around the outside edge of the cake, holding in the marshmallow frosting, ganache, and graham cracker layers inside. You can use any flavor of frosting for this.
How to Make a S’mores Cake, Layer By Layer
To start, you’ll prepare and bake the chocolate cake layers. It’s pretty much a one-bowl chocolate cake that comes together super quickly. All you really need is a whisk; no need to pull out the mixer. And don’t be afraid of the thin batter. It’s absolutely correct and makes the most wonderful chocolate cake.
Afterward, bake the cakes until a toothpick comes out clean, and let them cool before you assemble your s’mores cake.
Graham Cracker Crumbs
The next thing you’ll put together are the graham cracker crunchies:
- Combine. Mix together the crumbs, sugar and butter.
- Bake. Spread the crumbs out on a baking sheet. Bake for 8-10 minutes, cool, and you’re ready to go.
Marshmallow Frosting
Making the toasted marshmallow frosting is much like making any other buttercream, but perhaps even simpler.
- Toast the marshmallows. Place the marshmallows on a sheet pan under the broiler for a minute, or until browned.
- Make the frosting. Combine butter with marshmallow fluff and powdered sugar, then add the toasted marshmallows.
Chocolate Ganache
The chocolate ganache is next.
- Melt the chocolate. Heat the cream and pour it over the chocolate chips. Allow the heat from the cream to melt the chocolate.
- Whisk. Whisk until smooth, and you’ve got your ganache.
Assembling the Cake
Lastly, you’ll whip up a batch of vanilla frosting, and it’s time to build the s’mores cake! There are two filling layers between the three cake layers. It starts with a layer of ganache, then the toasted marshmallow frosting, and finally the graham cracker crumbs. All of that is held in place by a vanilla frosting dam.
What Does a Frosting Dam Do?
While the marshmallow buttercream is relatively thick, I wanted to ensure everything stayed in place and the cake remained stable. The best way to do this is by using a thick, stable frosting to create a dam around the outside edges of the cake layers. I talk more about cake dams in this post on how to build a cake if you’re interested in understanding that more.
How to Decorate a S’mores Cake
Once all the layers are together, frost the outside of the cake with the remaining marshmallow frosting (see how to frost a smooth cake). To decorate:
- Make a skirt of graham cracker crumbs. Press any remaining graham cracker crunchies around the bottom of the cake.
- Pour over the ganache. Add your chocolate drip using the remaining chocolate ganache.
- Add more toasted marshmallows. The finishing touch is to add the toasted marshmallows around the top of the cake and use a kitchen torch to toast them (I use this butane torch).
Proper Storage
- Room temperature. This s’mores cake can be stored covered at room temperature for up to 2 days. Keep it in a cake carrier or another airtight container.
- Refrigerate. You can also keep the finished cake in the fridge for 3-4 days. I still recommend taking it out of the fridge 30 minutes or so before serving, so it can come back to room temperature.
More S’mores Desserts to Love
S’mores Cake
- Prep Time: 2 hours
- Cook Time: 40 minutes
- Total Time: 2 hours 40 minutes
- Yield: 12–14 slices 1x
- Category: Dessert
- Method: Oven
- Cuisine: American
Description
This s’mores cake is an amazing combination of moist chocolate cake, toasted marshmallow buttercream, graham cracker crunchies and chocolate ganache! If you’re a s’mores lover, this cake is definitely for you!
Ingredients
Chocolate Cake
- 2 cups (260g) flour
- 2 cups (414g) sugar
- 3/4 cup (85g) natural unsweetened cocoa powder
- 2 tsp baking soda
- 1 tsp salt
- 2 large eggs
- 1 cup (240ml) milk
- 1 cup (240ml) vegetable oil
- 1 1/2 tsp vanilla
- 1 cup (240ml) hot water
Graham Cracker Crunchies
- 3/4 cups (100g) graham cracker crumbs (about 6 full sheet graham crackers)
- 1 1/2 tbsp (20g) sugar
- 1/4 cup (56g) unsalted butter, melted
Toasted Marshmallow Frosting
- 1 3/4 cups (392g) unsalted butter, room temperature
- 3 1/4 cups marshmallow fluff*
- 6 cups (690) powdered sugar
- 1 1/2 cups mini marshmallows
Chocolate Ganache
- 9 oz (1 1/2 cups) semi-sweet chocolate chips
- 3/4 cup (180ml) heavy whipping cream
Vanilla Frosting
- 3/4 cup (168g) unsalted butter, room temperature
- 3 cups (345g) powdered sugar
- 1 tsp vanilla extract
- 1 tbsp milk or cream
Instructions
Make the chocolate cake:
- Prepare three 8 inch cake pans with parchment paper circles in the bottom, and grease the sides. Preheat oven to 300°F (148°C).
- Add all dry ingredients to a large bowl and whisk together.
- Add eggs, milk and vegetable oil to the dry ingredients and mix well.
- Add vanilla to boiling water and add to mixture. Mix well. The batter will be very thin.
- Divide batter evenly between cakes pans and bake for 30-33 minutes, or until a toothpick comes out with a few crumbs.
- Remove cakes from oven and allow to cool for about 5 minutes, then remove to cooling racks to cool completely.
Make the graham cracker crunchies:
- When the cakes are cooled and you’re ready to build the cake, preheat oven to 350°F. Line a cookie sheet with parchment paper or a silicone baking mat and set aside.
- Combine the graham cracker crumbs, sugar and melted butter and stir until well combined. Spread the crumbs evenly onto the prepared cookie sheet.
- Bake for 8-10 minutes, then allow to cool. Set aside.
Make the toasted marshmallow frosting:
- To make the frosting, toast the marshmallows under the broiler for about 1 minute, or until toasted. Remove from the oven and set aside to allow them to cool completely.
- Add the butter to a large mixer bowl and beat until smooth.
- Add the marshmallow fluff to the butter and beat until well combined.
- Add about half of the powdered sugar to the butter mixture and mix until well combined and smooth.
- Add the remaining powdered sugar and mix until well combined and smooth.
- Add the cooled toasted marshmallows and mix until well combined. If the marshmallows are quite sticky, break them apart into smaller pieces before adding them to the frosting. Set aside.
Make the chocolate ganache:
- Add the chocolate chips to a medium sized bowl.
- Heat the heavy whipping cream until it just begins to boil, then pour it over the chocolate chips.
- Allow the chocolate and cream and to sit for 3-5 minutes, then whisk together until smooth. Set aside.
Make the vanilla frosting:
- Add the butter to a large mixer bowl and beat until smooth.
- Add about half of the powdered sugar and mix until well combined and smooth.
- Add the vanilla extract and cream and mix until well combined.
- Add the remaining powdered sugar and mix until well combined and smooth.
Build the cake:
- Remove cake domes from the tops of the cake with a large serrated knife. See my tips on how to level a cake and how to stack a cake.
- Place the first layer of cake on a cake plate or cardboard cake circle. Pipe a dam of vanilla frosting around the outer edge of the cake. This dam will help keep all of the filling in place so that nothing seeps out or doesn’t stay in place.
- Add about 6 tablespoons of chocolate ganache to the top of the cake and spread it into an even layer.
- Add one cup of marshmallow frosting to the top of the ganache and spread into an even layer.
- Add 1/2 a cup of graham cracker crunchies to the top of the frosting and spread evenly.
- Add the second layer of cake, another dam of vanilla frosting, then another layer of ganache, marshmallow frosting and graham cracker crunchies.
- Top the cake with the final layer of chocolate cake. Refrigerate the cake for about 30 minutes or so to make sure everything is stable.
- Use the remainder of the marshmallow frosting to frost the outside of the cake. Feel free to use my tutorial for frosting a smooth cake.
- Press the remaining graham cracker crunchies into the bottom part of the cake.
- Use the remainder of the chocolate ganache to add the chocolate drip to the cake. See my tutorial for how to make a chocolate drip cake. It will have cooled off by now, so you’ll want to carefully heat it back up in the microwave.
- Add some mini marshmallows to the top of the cake and use a kitchen torch to toast them.
- Refrigerate cake until ready to serve. Cake is best when stored in an air tight container. Serve cool, but not cold and finish leftovers within 3-4 days.
Notes
*I used almost all of two 7 oz jars of marshmallow fluff
Nutrition
- Serving Size: 1 Slice
- Calories: 1193
- Sugar: 133.9 g
- Sodium: 412.5 mg
- Fat: 61 g
- Carbohydrates: 164.4 g
- Protein: 6.6 g
- Cholesterol: 130.1 mg
Enjoy!
Marshmallow buttercream modified from Cookies and Cups
I’m rating this 5 stars, because it was so easy to follow. The chocolate cake portion is amazing! I am keeping it as my go to for future chocolate cakes and cupcakes, so moist and perfect!
I made this cake for my daughter’s birthday because she LOVES s’mores and marshmallows (personally I am not a fan) so for me the marshmallow filling was a bit rich and too sugary, but for all (and I do mean all) of the other guests, birthday girl included, the cake tasted amazing!
This chocolate cake was AHHHMAZING. This will be my forever go to chocolate cake recipe from now on. I should have listened to my better judgment because I tweaked the recipe a bit to add the chocolate cake in the middle of two graham cracker batter layers. I wish I would have stuck with every layer being chocolate because that in combination with the graham cracker crunchies were the stars!! Many compliments were received on those! I also did a homemade torched marshmallow fluff frosting. I’m going to come back to this recipe and try it exactly as is! I’m sure it will be an absolute winner! Thanks for the recipe!
So glad you enjoyed it!
Hi Lindsay – I made this cake for my daughter’s birthday recently and it turned out PERFECTLY! Your directions were concise and the tutorials were an extra help! It is an over-the-top sweet cake but done perfectly to mimic S’mores 🙂 Thanks!
I’m so glad to hear you were happy with it!
Well tried it once- won’t be making it again!! Frosting is sweet- not much of a marshmallow taste- and hard to put on the cake! Ended up going and buying a birthday cake for my son😕
This is the best chocolate cake I’ve ever made, but it’s so tender that sometimes the layers collapse. Is there anything I can do to avoid this because I really want to keep using this recipe!
Collapse as in break apart when moving it around? Or something else? I don’t typically have trouble, you just have to be gently with it. Are you letting the layers cool completely before working with them? You could also refrigerate them for a bit to firm them up before working with them. There are also cake lifters you could use. I hope that helps!
I’m so sorry! I didn’t mean to comment this on your post!
Why is there an asterisk by the marshmallow fluff in the marshmallow frosting part? I made it, and the marshmallow frosting was WAY to sticky and sweet.
The asterisk is to let you know that there’s a note below, which tells you how many jars of fluff you’ll need. As for the frosting, it’s definitely sweet. Marshmallows are pretty much sugar so that makes sense. They are also sticky, so the frosting will be a little bit too. But I don’t remember it being too sticky to work with at all. Did you add the full amount of powdered sugar?
Your cake looks gorgeous. I really love the way each layer is matched with each other <3
Hi Lindsay have a question how come most of your cake recipes you use all purpose flour instead of cake flour
It’s just a preference. I personally prefer the taste and texture of cakes that use all purpose.
Thanks but I can use cake flour instead
Yes
Here in SA where I live, we don’t get heavy cream anymore to make ganache. I’ve tried using normal whipping cream, but it does not work well. What would you recommend as a substitute for heavy cream, or how can I make my own? Thanks for your help.
I’m not sure what a substitute would be. The main difference in the creams is the amount of fat. Heavy cream is about 35% fat, so if you can find something like that, it should be fine. Maybe coffee creamer? The other option would be to use less of the cream that you have available and play around with the amount until you have the right consistency.
In the section of cake it calls for 1cup milk and under the section to assemble cake it mentions to add buttermilk, does the cake call for milk or buttermilk?
You could technically use either, but I used regular milk in this cake. I’ve updated the instructions. Thanks!
Yikes! I have to blow more than half of my daily allowance of calories on one slice?! It looks like it could be worth it.
Most of that is the frosting and the powdered sugar in it. Good thing cakes like this are a special treat and not an every day thing!
Hello, can I make this entire into a 9 x 13 cake?
Technically yes, I’m just not sure of exact measurements for the filling, etc. For the cake, here’s a place where I used it as a 9×13 for guidance on baking time. https://www.lifeloveandsugar.com/baileys-chocolate-poke-cake/
Do you have a chocolate cake recipe that is more of a milk chocolate cake? I searched for a milk chocolate cake on the site and it did not show any. I then searched chocolate cakes and there is many and of course they all made me hungry! I thought it would be easier to ask. Thank you so much.
This cake looks scrumptious and reminds me of camping.
This is personally my favorite chocolate cake, but if you’d like something a little less intensely chocolate, I’d try a butter-based chocolate cake, like this chocolate cake.
Hi, I cant find marshmallow fluff where I live. Is there a substitute I can use
Not that I know of, I’m sorry.
p.s. I have a birthday coming up next month….just saying.
haha! Will you live in Jacksonville yet? We might have to arrange a bday gathering 🙂
I can’t believe I am doing this, but I now have a new request for a dessert.
Hi Lindsay,
Let me tell you I made this cake 7/20/20 and it was some work in it. I was amazed that I could make it and it looks just like your only thing I didn’t put much of chocolate ganache on top with marshmallows.
Wonderful! So glad you enjoyed it!
Hey lindsay can i use milk chocolate instead of the dark chocolate in this cake? i am dying to make this but am not a huge fan of dark chocolate
Hey Kristie! Yes, you can use milk chocolate, but only use 4 ounces of heavy cream for 8 ounces of milk chocolate. I hope you like it! 🙂
I am drooling… and reaching for the insulin 🙂
Haha! Thanks!