S'mores Cake

4.88 from 8 ratings

This s'mores cake is made with moist chocolate cake layers, buttery graham cracker crust, toasted meringue buttercream, and rich chocolate ganache.

Prep Time1

Cook Time33

Additional Time30

Total Time2 3

Course: Cakes

Cuisine: American

Servings: 24 servings

Calories: 541kcal

Author: Chelsey White

Equipment

Rubber Spatula
3 8-inch cake pans
Parchment Paper
Food processor
10-inch Greaseproof Cake Board or a Flat Plate
Whisk
Stand Mixer with Whisk Attachment
Large Metal Bowl
Kitchen Torch
Kitchen Thermometer

Ingredients

Chocolate Ganache Filling

1/2 cup heavy whipping cream 120g
2 cups milk chocolate chips 360g
1/4 cup unsalted butter, room temperature 56g
2 Tbsp light corn syrup - optional 40g
1/2 tsp fine salt 3g

Graham Cracker Crust

2 cups graham cracker crumbs 200g
1/2 cup unsalted butter, melted 113g
1/3 cup granulated sugar 66g
1/4 tsp fine salt

Chocolate Cake Ingredients

2 cups all-purpose flour 260g
2 cups granulated sugar 400g
3/4 cup unsweetened cocoa powder, sifted 75g
2 tsp baking powder 8g
1 1/2 tsp baking soda 9g
1 tsp instant coffee or espresso, optional
1 tsp fine salt 6g
1 cup water, warm 240g
1 cup buttermilk, room temperature 240g
1/2 cup vegetable or canola oil 110g
2 large eggs, room temperature 112g
1 tsp vanilla extract or vanilla bean paste 4g

Toasted Meringue Buttercream

8 large egg whites, room temperature 240g
2 1/2 cups granulated sugar 500g
2 Tbsp light corn syrup (optional) 40g
2 cups unsalted butter, room temperature 454g
1 Tbsp vanilla extract or vanilla bean paste 15g
1/2 tsp fine salt 3g

Additional Decorations (optional)

1/3 cup milk chocolate, melted and cooled 60g

Instructions

Chocolate Ganache Filling

This ganache needs about an hour to thicken, so I recommend making it before the cake layers if possible! I usually make it the night before. Heat 1/2 cup of heavy cream in a heatproof bowl in the microwave for 45 seconds, until it just begins to bubble and steam. If you don't have a microwave, you can also use a double boiler to heat the cream.
Gently pour 2 cups of milk chocolate chips into the heavy cream. Make sure the chips are fully covered with cream. Let the mixture sit for 1 minute. If you want to use dark (60-65% cocoa) chocolate chips, use 1 1/3 cups (240g) and 1 cup of heavy cream.
Stir slowly until the cream and chocolate combine and the mixture is smooth. If any bits of chocolate aren't fully melted, heat the mixture again for 10 seconds and stir until smooth.
Then mix in 1/4 cup of room temperature unsalted butter, 2 Tbsp corn syrup (optional), and 1/2 tsp fine salt until combined.
Cover with plastic wrap to prevent the ganache from forming a skin, then set aside to cool to room temperature. You can pour the mixture into a shallow, wide tray to help it cool faster if you're in a rush.

Graham Cracker Crust

Preheat the oven to 350°F/175°C. Line three 8-inch cake pans with parchment paper rounds, and spray the sides of the pans with non-stick cooking spray or baking spray.
In a large bowl, mix together 2 cups of graham cracker crumbs, 1/2 cup of melted butter, 1/3 cup of granulated sugar, and 1/4 tsp of fine salt.
Divide the mixture evenly between the prepared pans (about 120g per pan), and press it into an even layer in each pan. Bake for 8-10 minutes, then set aside to cool.

Chocolate Cake Layers

Sift or whisk together 2 cups flour, 2 cups granulated sugar, 3/4 cup cocoa powder, 2 tsp baking powder, 1 1/2 tsp baking soda, 1 tsp fine salt, and 1 tsp instant espresso or coffee (optional) in a large bowl. Set aside.
In a separate, large bowl, add 1 cup warm water, 1 cup buttermilk, 1/2 cup oil, 2 eggs, and 1 tsp vanilla and whisk together until fully incorporated.
Whisk the dry ingredients into the wet ingredients until they're just combined, and the batter is smooth.
Pour the batter evenly (about 475g per pan if you're making 3 layers) between the 3 cake pans, pouring it directly onto the crust. Bake for 24-27 minutes or until a toothpick comes out with a few moist crumbs.
Let the pans cool for 10 minutes, then run a small offset spatula around the perimeter of the pan to separate the cake from the pan.
Place the cake pans into the freezer for 30 minutes to accelerate the cooling process. This helps lock in the steam and makes the layers extra moist. If you don't have room in the freezer, place the cake pans on a wire rack and let them cool fully before removing them.
Once the layers are fully cooled, carefully flip the pans and remove the layers. These cake layers bake up pretty flat, so leveling them is optional, but I like to level them with a serrated knife to make the cake easier to fill and frost.
If you make these cake layers in advance, let them thaw for about 15 minutes before making the cake. The cake layers should still be slightly cold to the touch, which will make it easier to assemble the cake.

Toasted Meringue Buttercream

While the cake layers bake and cool, make the toasted meringue frosting. Before making this frosting, be sure to thoroughly clean your mixing bowl. If there’s any grease, it can make it difficult to whip up the meringue.
In a medium-sized pot, add about 1 inch of water and bring to a simmer. Add 8 egg whites, 2 1/2 cups of granulated sugar, and 2 Tbsp of light corn syrup (optional) into a large metal bowl. Place the bowl on top of the pot filled with simmering water. The bowl should create a seal over the pot. Make sure the water isn’t actually touching the bottom of the bowl, or it can cook the egg whites.
Whisk the mixture constantly for about 3 minutes, until it reaches 160°F/71°C. You can test the mixture to see if it’s ready by rubbing a tiny bit between your fingertips. The sugar should be fully dissolved, and it should feel super smooth and hot to the touch.
Once it reaches this stage, lift the bowl away from the pot and dry the bottom with a towel. Pour the mixture into the metal bowl of a stand mixer and beat on a medium-high speed with a whisk attachment. Mix for about 10 minutes, or until you have stiff, glossy peaks that stick straight up. While the meringue whips, I like to add something cold around the base of my bowl. I find the meringue stays quite warm while it whips up, and placing a bag of frozen veggies around the base of the bowl helps cool it back to room temperature. This can prevent your buttercream from becoming soupy when you add the butter later.
Then use a kitchen torch to toast the top of the meringue in your bowl. Turn the mixer on medium speed to incorporate the toasted bits. Repeat this process a few times until you can see little bits of toasted meringue incorporated throughout the mixture.
Gradually mix in 2 cups of unsalted butter, 1 Tbsp vanilla extract, and 1/2 tsp fine salt on a medium speed. Scrape the sides and bottom of the bowl with a rubber spatula as needed. The frosting should have a thick, whipped consistency once all the butter is mixed in. If it looks lumpy or broken, keep mixing until it looks fluffy and thick. If it doesn't seem to come together after an additional 10 minutes of mixing, check out the troubleshooting section in the post above.

S'mores Cake Assembly

Place the first cake layer on a greaseproof cake board or large flat plate, using a small dab of buttercream to hold it in place.
Spread half of the chocolate ganache on top of the first cake layer, then top this with a thick layer of toasted meringue buttercream. Repeat with the next cake layers, then place the third cake layer on top. If the stacked cake feels soft or unstable, chill it for about 20 minutes in the freezer or 30 minutes in the fridge before frosting.
Use the remaining buttercream to cover the cake in a thick layer of toasted meringue buttercream. Use a large offset spatula or the back of a spoon to create a textured look around the cake.
If desired, drizzle the melted and cooled milk chocolate over the frosted cake while it is at room temperature but still fluid. Use the back of a spoon or an offset spatula to gently swirl it into the buttercream for a marbled finish.

Video

Notes

I highly recommend making your cake layers in advance and freezing them. It breaks the process up and makes it more approachable.

You can make your frosting ahead of time, too, or save any leftover frosting! It can be stored in an airtight container in the fridge for up to a week or in the freezer for up to 3 months. Be sure to give it a good stir once it thaws to get the consistency nice and smooth again.

A frosted cake can last in the fridge for up to a week, or in the freezer for up to a month. The buttercream locks in all the moisture, keeping the cake fresh and delicious!

If you cut into the cake and have leftovers, use any remaining frosting to cover the cut section to keep it moist and store it in the fridge for up to a week.

Nutrition