S’mores Cake with Toasted Marshmallow Buttercream Recipe

Recipe By:
Whitney DePaoli

Add a little campfire magic to your baking and wow family and friends with this delicious refresh of a classic taste combo from Whitney DePaoli of sugarandsparrow.com. Consisting irresistible layers of Graham cracker cake filled with toasted marshmallow buttercream, yep you read that right, TOASTED marshmallow buttercream, milk chocolate ganache and vanilla buttercream this sounds heavenly, right? But, there’s more—we’re going to top this crowd pleaser with a trendy milk chocolate drip, and finish with toasted marshmallow meringue flourishes!

Like Whitney, we’re big fans of highlighting a cake’s flavor profile by decorating with its main ingredients, in this case crushed Graham crackers, a milk chocolate ganache drip, and toasted marshmallow meringue flourishes. Use Wilton tips 1M and 4B to pipe the meringue before toasting, you’ll love how this recipe holds its shape. Its super easy to make, pipes like a dream, and looks gorgeous when toasted!

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

Note: All ingredients should be at room temperature before starting

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
2 cups (410g) caster sugar
5 large eggs, room temperature
1 1/2 tbsp vanilla extract
1/2 cup (112g) sour cream
1 1/2 cup (360ml) whole milk

Toasted Marshmallow Buttercream

8 large marshmallows
1/2 cup (113g) unsalted butter
1/2 cup (60g) powdered sugar (icing sugar)
1/2 tsp vanilla extract
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 (double cream)

Vanilla Buttercream

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

Marshmallow Meringue Topping

3 large egg whites
3/4 cup (150g) powdered sugar (icing sugar)
1/4 tsp cream of tartar
1 tsp vanilla extract

Method

Make the Graham Cracker Cake

Preheat the oven to 180˚C/160˚C fan/350˚F/gas mark 4 and prepare three 6 inch (15cm) cake pans by spraying the sides with cooking spray and fitting a parchment or wax paper circle to the bottom of each pan.
Grind the Graham crackers into a crumbs by either using a food processor or placing them into a large zip lock 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.
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.
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 thirty seconds. Do not over mix. Pour batter into prepared pans (about ⅔ full).
Bake for thirty-five to forty-five minutes or until a toothpick inserted into the center comes away clean. Cool 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

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 thirty seconds, then whisk 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

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

Make the Vanilla Buttercream

In a stand mixer with the paddle attachment, beat butter on high for until it’s fluffy and almost white in color, about seven 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

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 four minutes.
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 six 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

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.
Crumb coat the cake with vanilla buttercream and place it into the refrigerator for fifteen 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.

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 are ready to use them, bring 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 are ready to use it, bring back to room temperature. You can microwave it in small (ten to fifteen 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.

Enjoy!