for 8 servings
2 ½ cups (435 g) semi-sweet chocolate chips
2 cups (480 mL) heavy cream, hot
3 cups (255 g) marshmallow fluff, divided
3 tablespoons milk, divided
29 graham crackers, plus 2 graham crackers, crumbled, divided
1 chocolate bar, chopped, for deoration
- In a large heatproof bowl, pour the hot heavy cream over the semisweet chocolate chips. Let stand for 30 seconds, then whisk together for 1 minute, or until thick and smooth.
- Place 1 cup (85 g) of marshmallow fluff in a medium heatproof bowl and place the remaining fluff into a separate medium heatproof bowl. Add a tablespoon of milk to the bowl with 1 cup (85 g) of fluff and the remaining 2 tablespoons milk to the bowl with the remaining fluff.
- Microwave each bowl of fluff for 15 seconds.
- Remove the bowls from the microwave and use a fork to stir the milk into the fluff until it is thick and smooth. Cover the bowl with less fluff and store in the fridge – it will be used later for decoration.
- Line a 5x8-inch (13x20cm) loaf pan with parchment paper and place a row of graham crackers on the bottom of the pan. Pour a thin layer of the marshmallow fluff over the graham crackers and use a spoon or spatula to spread the mixture evenly. Place another row of graham crackers on top of the fluff, then pour a thin layer of the chocolate ganache over the crackers and use a spoon or spatula to spread an even layer. Repeat three more times.
- Cover and chill in the fridge overnight.
- Remove the cake and reserved marshmallow fluff from the fridge. Use the parchment to lift the cake out of the loaf pan.
- Microwave the leftover marshmallow fluff mixture for 15 seconds, then use a spatula to spread the fluff over the cake in an even layer.
- Optional: use a small kitchen torch to gently toast the marshmallow topping. Sprinkle crumbled graham cracker and chocolate chunks over the top of the cake.