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S’mores Cake takes everything you love about a gooey campfire s’more and stacks it into a tall, show stopping layer cake, and it is the dessert my girls request every single summer. Graham cracker yellow cake layers get a hot fudge filling, fluffy toasted marshmallow buttercream, and a glossy chocolate ganache drip on top. If you love that campfire flavor, our Amish s’mores whoopie pies are another fun treat to try.
It looks bakery fancy, but it starts with a boxed cake mix shortcut so anyone can pull it off.
S’mores Cake Quick Look
- 🕒 Prep Time: 30 minutes
- 🌡️ Cook Time: 25 minutes
- ⏳ Total Time: 55 minutes
- 🍽️ Serving: 14 servings
- ⚡ Calories: 1108kcal
- 🌶️ Flavor Profile: Sweet, toasty, and chocolatey with graham, marshmallow, and fudge in every bite
- ✋ Difficulty: Intermediate, a fun weekend bake worth the effort
Quick Answer
Bake graham cracker yellow cake layers, then toast mini marshmallows until golden. Beat the toasted marshmallows into a butter and powdered sugar buttercream for a true s’mores flavor. Stack the cooled cake layers with hot fudge and marshmallow buttercream, frost the outside, and finish with a chocolate ganache drip plus graham crackers, marshmallows, and chocolate squares on top.
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Why This Recipe Works
Click to see the technique science
- A cake mix shortcut. Starting with boxed yellow cake mix plus graham cracker crumbs gives you a tender, graham flavored layer cake without measuring out a dozen pantry staples.
- Toasted marshmallow buttercream. Broiling the marshmallows first and beating them into the buttercream gives the frosting that real toasted campfire flavor instead of just sweetness.
- A hot fudge filling. A layer of hot fudge between the cakes melts slightly into the crumb so every slice has that gooey chocolate center.
- The ganache drip is the wow factor. A simple two ingredient chocolate ganache poured around the edge turns this into a bakery worthy showstopper.
- It feeds a crowd. A tall three layer cake serves up to 14, making it perfect for birthdays, cookouts, and summer parties.
Why You’ll Love This Recipe
- It tastes exactly like a gooey campfire s’more in tall, sliceable cake form.
- It starts with a boxed cake mix, so it is easier than it looks.
- It is a guaranteed showstopper, just like our no churn s’mores ice cream at a summer party.
Key Ingredients
A few smart shortcuts give this s’mores cake big campfire flavor with less work.
- Yellow cake mix and graham cracker crumbs: The base of the layers, combining for a tender cake with real graham flavor.
- Mini marshmallows: Toasted under the broiler, then beaten into the buttercream and piled on top for that classic s’mores look.
- Hot fudge: Spread between the layers for a gooey, melty chocolate center.
- Butter and powdered sugar: Whipped with the toasted marshmallows into a fluffy, sweet buttercream frosting.
- Chocolate chips and heavy cream: Melted together into the glossy ganache drip that finishes the cake.
See recipe card for exact quantities.
Variations and Substitutions
Make this s’mores cake your own with a few easy swaps.
- Use a chocolate cake mix instead of yellow for a double chocolate s’mores cake.
- Bake it as a sheet cake in a 9 by 13 pan if you want something simpler to serve.
- Swap the hot fudge filling for a layer of chocolate cream cheese frosting if you prefer.
- Torch the marshmallows on top with a kitchen torch for an extra toasty, golden finish.
How to Make S’mores Cake
- Preheat the oven and whisk together the yellow cake mix, graham cracker crumbs, water, oil, and eggs until you have a smooth batter.
- Divide the batter between greased round cake pans and bake until a toothpick comes out clean. Let the layers cool completely.
- Spread mini marshmallows on a foil lined pan and broil until golden and toasted, watching closely so they do not burn.
- Beat the softened butter with the toasted marshmallows in a stand mixer until combined and creamy.
- Add the powdered sugar a little at a time and whip until the marshmallow buttercream is light and fluffy.
- Stack the layers with hot fudge and buttercream, frost the outside, then add the chocolate ganache drip and s’mores garnishes.
Recipe Tips & Tricks
- Cool the cake layers completely before frosting, or the marshmallow buttercream will slide right off.
- Watch the marshmallows closely under the broiler, since they go from toasted to burnt in seconds.
- Let the ganache cool slightly until it is pourable but not hot, so it sets in pretty drips instead of running off.
- Use an offset spatula for the smoothest frosting, and chill the cake briefly before the drip if it feels soft.
- Crush extra graham crackers to press around the bottom edge for a polished, bakery style finish.
- Make it ahead by baking the layers a day early and wrapping them tightly until you are ready to assemble.
Serving Ideas and Suggestions
This s’mores cake is the centerpiece of any summer celebration, so slice it tall and serve it on a pretty stand where everyone can admire the ganache drip and toasty marshmallows.
It is rich, so a thin slice goes a long way, especially next to a scoop of vanilla ice cream or our no churn s’mores ice cream.
Round out a dessert table with our mini cheesecakes and a creamy tiramisu pie for a spread that covers every craving.
S’mores Cake FAQs
Yes. You can swap the boxed mix for your favorite from scratch yellow or vanilla cake batter. Just fold in the graham cracker crumbs and bake as usual for that signature s’mores flavor.
Spread mini marshmallows on a foil lined baking sheet and broil for 1 to 2 minutes, watching the entire time. They should be golden brown and puffed. You can also use a kitchen torch.
Store the cake in an airtight container or cake keeper at room temperature for up to 2 days, or in the fridge for up to 5 days. Let chilled cake sit out before serving so it softens.
Yes. Bake and wrap the cake layers up to 2 days ahead, or freeze them for up to 2 months. Make the buttercream and assemble the day you plan to serve for the freshest result.
Runny buttercream usually means the butter was too warm or the toasted marshmallows were still hot. Use softened but cool butter, let the marshmallows cool, and chill the frosting briefly if needed.
Absolutely. Bake the batter in lined muffin tins for about 18 minutes, then top each cooled cupcake with marshmallow buttercream, a drizzle of ganache, and a graham cracker piece.
Made this s’mores cake? I would love to hear how it turned out, leave a comment and a star rating below and tell me what you celebrated with it!
S’mores Layer Cake
Ingredients
- 2 boxes 15.25 ounce yellow cake mix
- 2 cups graham cracker crumbs
- 2 cups water
- 1 ⅓ cups vegetable oil
- 6 eggs
- 11.75 ounce jar of hot fudge
- 4 sticks 2 cups unsalted butter, softened
- 2 pounds powdered sugar
- 4 cups mini marshmallows
- 1 cup semisweet chocolate chips
- 1 cup heavy whipping cream
- Garnish graham cracker crumbs, hershey bars, graham crackers, mini marshmallows, regular marshmallows.
Instructions
- Preheat the oven to 350 degrees F. Lightly grease three 8 inch cake pans.
- In a large mixing bowl combine the 2 cake mixes, graham cracker crumbs, water, oil and eggs. Whisk until smooth and all combined.
- Divide the batter evenly between the 3 pans.
- Bake at 350 for 20-25 minutes or until a toothpick inserted comes out clean.
- Let the cakes cool in the pans for 5 minutes before transferring from the pans to a cooling rack to cool the cakes completely.
- Meanwhile prepare the buttercream.
- Turn your oven to broil.
- Line a baking sheet with foil and spray with non-stick spray.
- Spread out the 4 cups of mini marshmallows on the baking sheet.
- Place the marshmallows under the broiler. Do not take your eyes off the marshmallows while they are under the broiler. It will only take them a minute to get toasted.
- Remove the marshmallows from the oven and immediately add to a large mixing bowl.
- To the bowl add your softened butter and using an electric mixer whip the butter and marshmallow together.
- Next carefully add the powdered sugar a little at a time.
- Once all the sugar is added, whip the frosting for 5-7 minutes until light and fluffy.
- Next prepare to frost your cake.Place a cake layer onto your serving plate or cake plate.
- Frost the top of that layer with a layer of the marshmallow buttercream.
- Top that with half of the hot fudge sauce. The buttercream and the fudge sauce will mix a little and that’s okay. Repeat with the next layer.
- Place the final layer on top and frost the whole cake with the marshmallow buttercream. If you like you can reserve some frosting and pipe a bit on the top for decoration.
- In a small microwave safe bowl warm your heavy whipping cream in 30 second increments until hot.
- Add your chocolate chips to the cream and let sit for 5 minutes before whisking together. Whisk until smooth and glossy.
- Let the ganache cool slightly and drizzle it around the top edge. You can also use a piping bag or ziploc bag with the tip snipped for this.
- Take some graham cracker crumbs and sprinkle them around the bottom half of the cake. I then decorate the top with graham crackers, hershey bars and more marshmallows though this is optional.
Notes
- Nutritional value does not include garnishes.
- This can be made in a 9×13-inch pan or into cupcakes, see how to do that above.
- We do not recommend freezing the assembled cake.
- Use already crushed graham cracker crumbs to cut time.
- If you do not want to make ganache, just top with more hot fudge.
- Make sure that your cake layers are cool before assembling.
Nutrition
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