Peanut Butter S'mores Brownies




Yield 15 large brownies

Graham cracker crust covered with fudgy brownies swirled with peanut butter and topped with melted marshmallows. Nothing says summer like s’mores over the campfire and these Peanut Butter S’mores Brownies take summer to the next level!

See notes for cutting the recipe in half!


Graham cracker crust:




Graham Cracker Crust:

  1. Preheat oven to 350° F. Lightly grease a 9x13 inch baking pan and line with parchment paper (the grease helps the paper hold tight to the pan. Or you can grease the pan and skip the paper*). Set aside.
  2. In a medium bowl, stir together graham cracker crumbs and melted butter until combined. Pour mixture into prepared pan and press firmly into the pan in an even layer. Bake 10-12 minutes until set and beginning to lightly brown.


  1. In a medium bowl, whisk together flour, cocoa powder, and salt. Set aside.
  2. In a large bowl, whisk together melted butter, vegetable oil, and sugar. Add eggs and vanilla extract to mixture and whisk again until combined and lighter in color.
  3. Gently mix dry ingredients into the wet mixture until just combined (do not overmix).
  4. Lightly fold 1 cup peanut butter and 1 cup chocolate chips into brownie batter. There should be streaks of peanut butter.
  5. Pour brownie batter over graham cracker crust in pan. Drizzle the remaining peanut butter over the brownie mixture and use a butter knife to lightly drag and swirl the peanut butter into the brownie mixture. Sprinkle with remaining chocolate chips.
  6. Bake for about 30-35 minutes until brownies are set and not jiggly but still soft and fudgy in the center. If testing with a toothpick, the toothpick will come out dirty (brownies will continue to cook as they sit in the hot pan).
  7. Remove from oven and cover brownies with marshmallows. Return to oven and broil on low for 1-2 minutes until marshmallows are golden brown. Keep a VERY close eye on your marshmallows as they brown quickly!
  8. Remove from oven and allow to cool for at least 30 minutes (they will be very gooey when warm). Remove from pan, slice, and serve warm with a tall glass of milk!


  1. This recipe makes a large pan of thick brownies, which is perfect for a party or a family! But, if you would like to cut the recipe in half, you can certainly do so! Here are some tips:
    • Use an 8x8" square baking pan
    • Instead of 1½ sticks of butter, use 6 tablespoons of butter
    • Instead of 1/4 cup of oil, you would use 2 tablespoons of oil
    • Instead of 3 eggs, I recommend using 2 eggs (because you can't exactly cut an egg in half)
    • Bake graham cracker crust for 8-10 minutes until golden
    • Bake brownies for 20-22 minutes
  2. *Using parchment paper allows you to lift the brownies out of the pan. If you don't need or want to do that, you can simply grease the pan and skip the parchment paper.
  3. Tip for storing the brownies: Grease the inside of a sheet of tinfoil before placing it over the brownies; this will prevent the tinfoil from sticking to the marshmallows.

Courses Dessert

Cuisine American

Recipe by Modern Farmhouse Eats at