If you're a fan of the nostalgic and mouth-watering campfire favorite snack of graham crackers, chocolate, and marshmallows, then you simply cannot miss out on this fantastic s'mores brownie recipe. These brownies capture the same mouth-watering flavors of traditional s'mores and add an irresistible twist by incorporating them into a rich, chewy brownie. The best part? They're incredibly easy to make and are a fantastic hack for boxed brownie mixes. With this recipe, you'll be able to enjoy the ooey-gooey goodness of s'mores in brownie form and satisfy your sweet tooth in no time!

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Graham cracker crust

  • 180g graham crackers (about 12 sheets)
  • 6 tbsp (85g) unsalted butter melted



For the graham cracker crust:

  1. Preheat oven based on the package instructions of your brownie mix. Line a 9"x9" square baking pan with a parchment paper sling. Set aside.
  2. Place the graham crackers into the bowl of a food processor and pulse the graham crackers until it resembles fine crumbs. 
  3. Pour the melted butter on top of the graham cracker crumbs and pulse until fully incorporated and resembles wet sand. Alternatively, if you don't have a food processor, place the graham crackers into a zip top bag and use a rolling pin or pan to crush the graham crackers into fine crumbs. Transfer crumbs to a bowl, pour melted butter into the crumbs, and mix until the mixture resembles wet sand.
  4. Press the graham cracker mixture into the bottom of the prepared baking pan. Set aside.

For the brownies:

  1. Prepare the brownies per the package instructions. Pour half of the batter on top of the graham cracker crust and spread to the edges. Next, spread the homemade marshmallow fluff, or mini marshmallows, over the batter, then top with the remaining batter. It's ok if some marshmallow is peeking through.
  2. Place in the oven and bake per the package instructions of your box brownie mix. To prevent dry brownies, slightly underbake them then let cool in the baking pan. The brownies will continue to bake slightly as it cools.
  3. Using the parchment sling, remove brownies from the pan, slice, and enjoy!


  • Marshmallow fluff: If you are short on time and don't want to make your own marshmallow fluff, you can substitute mini marshmallows.
  • Storage: You can store these s'mores brownies in an airtight container for up to 3 days.