S’mores Cake

This S’mores Cake consists of a moist chocolate cake baked on a sweet graham cracker crust, with a chocolate ganache filling and a toasted marshmallow whipped cream filling, covered in a delicious graham cracker marshmallow buttercream and a chocolate ganache drip! (You may want to read that sentence again just to take in all the amazing elements of this ultimate s’mores cake!)

I’m a big fan of campfire s’mores, so of course I needed to find a way to make them in the winter, inside, in the oven, etc etc! S’mores in the Microwave, Oven S’mores, or Reese’s S’mores Dip are easy and quick for cravings. Or try my other s’mores variations like S’mores Cookies, S’mores Brownies, and S’mores Rice Krispies. Can you tell I love s’mores??

Why This Recipe Works

• All s’mores components represented. The chocolate, the graham crackers, and the mallows are all in this s’mores chocolate cake! And not just that, but each element is in the cake twice! When you bite into this cake, you’ll immediately say, “yep, that tastes exactly like s’mores!” (Which is exactly what my husband said when he tried it!)
• Indulgently delicious. I’m going to repeat myself here just because I want you to really take in just how amazing each element of this cake is: tender layers of chocolate cake. Sweet and thick graham cracker crust. Smooth chocolate ganache between each layer. Fluffy toasted marshmallow whipped cream oozing between the layers. Toasted marshmallow and graham cracker crumbs in the buttercream. Topped off with a chocolate drip and all the s’mores toppings you could dream of! I mean. Need I say more? 
• Bring the campfire indoors. This delicious s’mores cake is the best way to bring this favorite campfire food right inside during the summer and winter months! Not the right weather for campfire s’mores? S’mores cake. Don’t want to deal with bugs or campfire smells lingering? S’mores Cake! 

Ingredient Notes

• Graham Cracker Crumbs: You will need about 20 full graham cracker sheets for the crust and 9 full sheets for the toasted marshmallow frosting. 
• Unsalted Butter: Melted butter for the crust. If using salted butter omit the 1/4 tsp salt in the crust. For the buttercream, you’ll need the butter to be slightly soft but still cold. If using salted butter for the buttercream, do not add the pinch of salt. 
• Unsweetened Cocoa Powder: Unsweetened cocoa powder, also known as natural cocoa powder, is the lightest cocoa powder in color. Learn more about Best Cocoa Powders for Baking. 
• Buttermilk: The buttermilk is acidic, which means it will react with the baking soda to create a light and risen cake texture. It will also help keep things nice and moist. 
• Vegetable Oil: Cakes made with vegetable oil are much more moist than if made with butter. 
• Hot Water: The hot water is to bloom the cocoa powder. Blooming cocoa powder is adding hot liquid to cocoa. It brings out a richer and fuller chocolate flavor. 
• Marshmallows: You will need large marshmallows and mini marshmallows. Toasting the marshmallows brings out the toasted marshmallow flavor from traditional s’mores! 
• Powdered Sugar: Sift the powdered sugar to get the best and smoothest results in the buttercream frosting. 
• Heavy Cream: The heavy cream will be used to loosen up the buttercream and provide a fluffier texture. Then we will also use the heavy cream for the toasted marshmallow whipped cream filling between the layers of chocolate cake.

Step-by-Step Instructions

1. Make the graham cracker crust. Combine the graham cracker crumbs, melted butter, sugar and salt in a large mixing bowl. Stir until combined. Spray three 8-inch round cake pans with nonstick spray, line the bottoms with a circle of parchment paper and spray again. Divide the crust mixture evenly among the three pans and press firming into the bottom. Bake at 325°F for 4 minutes. Remove and let cool. 
2. Make the chocolate cake layers. Whisk the dry ingredients together in a medium bowl. Set aside. Add the eggs, buttermilk, vegetable oil and vanilla extract to the bowl of a stand mixer with the paddle attachment and mix until well combined. Add the dry ingredients to the wet ingredients and mix. Pour in the hot water and mix until combined. Divide the chocolate cake batter evenly among the three cake pans, pouring directly on top of the crusts. Bake at 325°F for 23-27 minutes or until a toothpick comes out with a few moist crumbs but no wet batter.
3. Let cool. Remove the cake pans from the oven and let cool in the pans for 10 minutes. Turn out onto a wire rack to cool completely.

4. Make the chocolate ganache. Add the chocolate chips to a heat-proof bowl. In a separate bowl, add the heavy cream. Microwave until hot and pour onto the chocolate chips. Let sit without stirring for 2 minutes. Then whisk until smooth.
5. Make the toasted marshmallow whipped cream. Place the marshmallows on a cookie sheet sprayed with nonstick spray. Broil until toasted (1-2 minutes depending on your oven – watch closely!). Add the toasted mallows and 2 teaspoons of heavy cream to a heat-proof bowl and mix until smooth. In a separate bowl, beat the heavy cream until stiff peaks form. Gently fold the marshmallow mixture into the whipped cream. Store in the fridge. 

6. Make the toasted marshmallow graham cracker buttercream. Toast the marshmallows on a sprayed cookie sheet in the oven on broil (1-2 minutes – watch closely!) Beat the butter in the bowl of a stand mixer until light in color and smooth. Add the fine graham cracker crumbs, salt and the toasted marshmallows (that are slightly cooled). Beat until the mixture is homogenous. Add the vanilla extract and mix while slowly adding the powdered sugar and heavy cream. Once all ingredients are added, beat on high speed for 3 minutes. 

7. Assemble the s’mores cake. Place a cake layer crust side down. Cover with a thin layer of buttercream then pipe a dam on the circumference of the cake. Spread a layer of chocolate ganache then fill with the toasted marshmallow whipped cream. Place the second cake layer on top and repeat. Add the next cake as the top layer, crust side down.

8. Crumb coat the cake. Frost the entire cake in a thin, thin layer of marshmallow buttercream (this is the crumb coat). And refrigerate or freeze for 10-15 minutes or until the buttercream is cold. 
9. Frost and decorate the s’mores cake. Frost the entire cake. Add the ganache for a chocolate drip cake look. Spread the ganache on top of the cake to create the chocolate covering on top. Use any leftover frosting for piping work on top. Add extra graham cracker sheets, toasted marshmallows and pieces of Hershey’s chocolate to the top for decoration! Enjoy! 

Recipe Tips

You may need to add a tablespoon or two of cream to get the ganache to a good drip consistency. When ready to add to the outside of the cake, I like to do a test drip on a glass cup to make sure it will drip down enough but not too much.

Be sure to not overfill the cake as it will seep out when you add the next layer and make the cake unstable and difficult to finish icing.

Use a food processor to get the fine crumbs for the graham cracker buttercream. 

In each of the marshmallow elements, the marshmallows need to become homogenous with their respective mixtures. The toasted marshmallows for the whipped cream will still be warm when combined with the heavy cream. Stirring that will loosen up the marshmallows and they will combine with the cream. Let that cool slightly before folding into the whipped cream so you don’t melt the whipped cream.

When beating the toasted marshmallows in with the buttercream, the marshmallows will break down and combine with the mixture. This will make it spreadable and able to be piped. We don’t use melted marshmallows, but they will and should incorporate into their mixtures and be smooth! 

Do not over bake the cakes. The chocolate s’mores cake is done when a toothpick in the center comes out with a few moist crumbs but no wet batter. If you pull the cakes out with some wet batter on the toothpick, the centers will sink because they aren’t baked enough. A clean toothpick could mean the cakes are over done. 

I use an offset spatula to gently spread the chocolate ganache on top of the cake. I used extra toasted marshmallows for decoration on top of the ganache. If you use a kitchen torch, just be careful not to melt the frosting!

Make Ahead, Storing, and Freezing

The toasted marshmallow buttercream frosting can be made ahead of time and stored in the refrigerator. It will need to sit at room temperature for 4-5 hours after refrigeration to become soft and spreadable again.

Store the toasted marshmallow whipped cream in the fridge until ready to use. If you have leftovers (or you just want all the mallow whipped cream so you make some more), store it in an airtight container in the fridge for 1-2 days. Enjoy as a graham cracker dip! 

If you aren’t going to assemble the cake right away, let the chocolate s’mores cake layers cool completely then double wrap in plastic wrap and store on a flat surface in the fridge for up to 1 day (maybe 2 max). If needing to store longer than that, I recommend freezing them. Let thaw in the fridge overnight before assembling. 

For more information on storing and freezing cakes, including how to freeze cake layers, buttercream and decorated cakes, check out my How to Store and Freeze Cakes guide!

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