S'mores Cake

S'mores Cake

The Spruce / Kristina Vanni & Eric Kleinberg

Prep: 25 mins
Cook: 35 mins
Chill: 90 mins
Total: 2 hrs 30 mins
Servings: 8 servings
Yield: 1 layer cake

S'mores are an American classic. A warm, toasted marshmallow sandwiched between two graham crackers and a perfectly melted square of chocolate is a gooey, melty, crispy, and sweet treat. This flavor profile is the basis for an impressive s'mores layer cake with a drippy ganache topping, and there are even extra s'mores as decoration on top!

Although graham crackers are the most traditional, you could put your own twist on s'mores by using vanilla wafer cookies, gingersnaps, or crumbled buttery sugar cookies instead. Typically milk chocolate is used, but if you prefer dark chocolate or even white chocolate those are also delicious and unique twists on the classic combination.

Serve this show-stopping cake at a birthday party, show it off at a potluck or bake sale, or end a barbecue on a festive note. It's a great way to enjoy the flavors of s'mores without the smoky campsite.


  • For the Chocolate Cake:
  • 1 (15.25-ounce) box chocolate cake mix
  • 1 cup water
  • 3 large eggs
  • 1/3 cup vegetable oil
  • For the Marshmallow Frosting and Graham Cracker Crumble:
  • 3 cups powdered sugar
  • 1 cup unsalted butter, softened
  • 1 tablespoon milk
  • 1/2 teaspoon vanilla extract
  • 1 (7-ounce) jar marshmallow fluff
  • 1/4 cup graham cracker crumbs
  • For the Chocolate Ganache:
  • 4 ounces semisweet chocolate chips
  • 1/3 cup heavy whipping cream
  • For the S’mores Garnish:
  • 16 graham crackers
  • 8 large marshmallows, halved
  • 8 chocolate bar pieces, or fun-size chocolate bars

Steps to Make It

Make the Cake and Frosting

  1. Gather the ingredients. Preheat the oven to 350 F. Grease and flour two 8-inch cake pans and set aside.

    S'mores Cake ingredients

    The Spruce / Kristina Vanni & Eric Kleinberg

  2. In a large mixing bowl, combine the cake mix, water, eggs, and oil until moistened. Beat at medium speed for 2 minutes.

    Chocolate cake ingredients in a mixing bowl

    The Spruce / Kristina Vanni & Eric Kleinberg

  3. Pour the batter into the prepared pans. Bake for 26 to 31 minutes. The cakes are done when a toothpick inserted in the center comes out clean.

    Chocolate cake in baking pans

    The Spruce / Kristina Vanni & Eric Kleinberg

  4. Cool in the pans on a wire rack for 15 minutes. Remove from pans and cool completely before frosting.

    Chocolate cakes cooling on racks

    The Spruce / Kristina Vanni & Eric Kleinberg

  5. To make the frosting, combine the powdered sugar, butter, milk, and vanilla in a large mixing bowl. Beat until fluffy. Beat in the marshmallow cream.

    Frosting ingredients in a bowl

    The Spruce / Kristina Vanni & Eric Kleinberg

  6. Place the first cake layer on the serving platter. Spread some of the marshmallow buttercream on top of the layer.

    Cake layer spread with frosting

    The Spruce / Kristina Vanni & Eric Kleinberg

  7. Sprinkle with the graham cracker crumbs.

    Graham cracker crumbs spread on top of frosting layer

    The Spruce / Kristina Vanni & Eric Kleinberg

  8. Top with the other cake layer and cover the cake with the remaining marshmallow buttercream frosting. Refrigerate to set, at least an hour.

Make the Ganache and Garnishes

  1. For the chocolate ganache, combine the semisweet chocolate chips and whipping cream in a small saucepan over low heat. Cook, stirring frequently, until the chocolate is melted and smooth. Cool for 5 minutes.

    Ganache ingredients in a pot

    The Spruce / Kristina Vanni & Eric Kleinberg

  2. Pour the ganache mixture on top of the chilled cake and allow it to drip down the sides of the cake.

    Chocolate ganache poured over cake

    The Spruce / Kristina Vanni & Eric Kleinberg

  3. Make the s’mores garnish. Toast the marshmallows over an open fire or using a kitchen torch to toast.

  4. Sandwich them between two graham cracker pieces with a small piece of a chocolate bar.

    Small S'mores for garnish assembled

    The Spruce / Kristina Vanni & Eric Kleinberg

  5. Place the s'mores garnish around the top of the cake.

    Decorated S'mores Cake

    The Spruce / Kristina Vanni & Eric Kleinberg

  6. Chill until ready to serve. Enjoy!

Recipe Variation

  • To make indoor s'mores, do not toast the marshmallows. Place half of the graham cracker squares on a microwave-safe plate and top with the chocolate and marshmallows. Microwave for 15 to 20 seconds or until marshmallows puff. Cover with remaining graham cracker squares and press together gently to secure.