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Marshmallow Frosting
Graham Cracker Cake with Chocolate Ganache and Marshmallow Frosting
Prep Time
25 mins
Cook Time
45 mins
Total Time
1 hr 10 mins
This dessert has all the flavors of S'mores in cake form. You can prepare the cake and ganache ahead of time, then frost with the marshmallow topping closer to serving time.
Servings: 24 pieces
Author: Mary Gillespie
  • 1/2 cup / 125 ml vegetable oil
  • 1/2 cup / 125 ml brown sugar
  • 1/2 cup / 125 ml granulated sugar
  • 2 eggs
  • 1/2 cup / 125 ml milk
  • 1 cup / 250 ml graham cracker crumbs
  • 1 cup / 250 ml all-purpose flour
  • 1/2 cup / 125 ml whole wheat flour
  • 1-1/2 teaspoons / 7.5 ml baking powder
  • 1/2 teaspoon / 2.5 ml salt
  • 2 cups / 500 ml chopped chocolate or chocolate chips
  • 2 tablespoons / 30 ml butter
  • 1 cup / 250 ml whipping cream 35% or full cream
Marshmallow Frosting:
  • 1/2 cup / 125 ml granulated sugar
  • 3 tablespoons / 45 ml water
  • 2 egg whites or 1/2 cup / 125 ml of pasteurized egg whites
  • Pinch salt
  • 1/2 teaspoon / 2.5 ml vanilla
  1. Preheat oven to 350 degrees F / 177 degrees C.
  2. Grease a 9x9-inch / 23x23 ml baking pan, and line with 2 pieces of parchment paper that have been cut long enough to hang over edges of pan by 1 inch / 2.5 ml. Place the first piece of parchment paper so that the edges overhang, then place the second piece so that it overhangs the other edges. The paper will form a cross in the pan.
  3. Beat oil and sugar until fully mixed and thick.
  4. Add the eggs one at a time and beat thoroughly after each addition.
  5. Add the milk and beat until smooth.
  6. In separate bowl, stir together graham cracker crumbs, all-purpose flour, whole wheat flour, baking powder and salt.
  7. Stir flour mixture into sugar mixture, and stir until combined.
  8. Pour batter into prepared pan and bake for 35-45 minutes, or until top is golden and a toothpick inserted in the center comes out clean.
  9. Remove from oven and let cool in pan for 5 minutes.
  10. Slip knife between the parchment paper and the baking pan to loosen. Using the overhanging paper, gently lift the cake onto a cooling rack. Leave the parchment paper on the cake and let cool completely.
  11. When the cake has cooled completely, gently lift back into the baking pan.
  1. Place chocolate and butter in mixing bowl.
  2. Heat cream in microwave or on stove top until bubbles appear around edges.
  3. Pour heated cream over the chocolate and let it sit for 5 minutes.
  4. Stir cream and chocolate together. At first it will look grainy, but it will start to become glossy and thick as the cream and chocolate come together.
  5. If there are still unmelted bits of chocolate, heat the mixture in the microwave for 10-20 seconds, or place over a pan of gently simmering water and stir until the chocolate has melted.
  6. Let the ganache cool for 10-15 minutes, then pour over the cooled cake that has been returned to the baking pan.The ganache will need to sit to set or firm up.
Marshmallow Frosting:
  1. Put sugar and water in small saucepan. Heat until the mixture comes to a simmer and the sugar has dissolved. DO NOT STIR. You can swirl the pan gently to move any clumps of sugar if needed.
  2. When the sugar has dissolved completely, pour the syrup into a glass measuring cup.
  3. While the syrup is cooking, place eggs whites in large metal or glass mixing bowl. Add the pinch of salt.
  4. Beat the egg whites until they form soft peaks.
  5. With the beater running, slowly pour the sugar syrup in a thin stream until all the syrup has been added.
  6. Beat the mixture on high speed for seven minutes. Add the vanilla and beat into the frosting.
  7. Spread frosting over the cooled ganache.
  8. If you want a toasted top, place the frosted cake under the broiler for 20-30 seconds.
Recipe Notes

You can use milk chocolate for the ganache. Reduce the amount of whipping cream to 2/3 cup and follow the instructions as given. Milk chocolate ganache may take longer to set.