Rocky Road Brownies
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These Rocky Road Brownies start with a boxed brownie mix and are layered with melted chocolate, marshmallows, and crunchy peanuts. The end result is a decadent, chewy treat with just the right mix of sweet and salty textures.
Easy Chocolate Marshmallow Brownies
If you’ve been around for a bit, you already know I love finding ways to take boxed brownies and turn them into something a little more fun (and if you’re new here, hi! I’m Mandy, and I love making boxed brownies feel fancy). These Rocky Road Brownies are another one of those simple upgrades. The combo of gooey marshmallows, melted chocolate, and salty peanuts hits that same sweet-salty-crunchy balance as my S’mores Brownies.
I got the idea for these after making another favorite, my Buckeye Brownies. I figured if peanut butter and chocolate work that well together, adding marshmallows and peanuts on top would just take it to the next level.
Ingredients
- Brownie mix + ingredients on the box – Makes the chocolatey base quick and easy. I used Duncan Hines Fudge
- Semi-sweet chocolate chips – Melt into a rich, smooth topping.
- Creamy peanut butter – Adds salty, nutty flavor to the topping.
- Unsalted butter – Helps melt and combine the topping ingredients.
- Mini marshmallows – Bring soft texture and classic rocky road flavor.
- Dry roasted, salted peanuts – Add crunch and a salty finish.
How to Make Rocky Road Brownies
- Prep and bake – Preheat the oven according to the brownie mix instructions and prepare a 9×9-inch pan. Mix and bake the brownie batter according to the directions on the box. Let cool in the pan for 15–20 minutes.
- Make topping – In a medium saucepan over medium-low heat, combine chocolate chips, peanut butter, and butter. Stir until smooth, then remove from heat and let it sit for 5 minutes.
- Fold in – Fold 2 cups of mini marshmallows and ¾ cup of peanuts into the warm chocolate mixture.
- Add topping – Spread the topping mixture over the cooled brownies. Sprinkle with the remaining ½ cup of marshmallows and ¼ cup of peanuts, pressing them in gently.
- Chill to set – Let cool completely at room temperature, then refrigerate for 2-3 hours before cutting.
Variations and Substitutions
- Different nuts – Swap the peanuts for chopped almonds, walnuts, or pecans for a different flavor or texture.
- Nut-free option – Use sunflower seed butter and omit the peanuts, or sub in pretzel pieces for crunch without nuts.
- White chocolate version – Replace the semi-sweet chocolate chips with white chocolate chips for a sweeter twist.
- Add crunch – Stir crushed graham crackers or crispy rice cereal into the topping for extra texture.
- Use homemade brownies – If you prefer, swap the boxed mix for your favorite homemade brownie base.
Tips for Success
- Let the brownies cool – Give them at least 15–20 minutes before adding the topping so it doesn’t melt too much into the base.
- Don’t skip the chill – Refrigerating helps the topping set and makes slicing much cleaner.
- Use fresh marshmallows – Older marshmallows can get dry or rubbery and won’t melt into the topping as well.
- Line your pan – Use parchment or foil with an overhang to make lifting and cutting easier.
- Cut with a warm knife – Run your knife under hot water and wipe it dry between slices for cleaner cuts.
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Rocky Road Brownies Recipe
Ingredients
- 1 (18-ounce) box brownie mix + ingredients listed on the box
- 1 1/2 cups semi-sweet chocolate chips
- 1/2 cup creamy peanut butter
- 1/4 cup unsalted butter
- 2 1/2 cups mini marshmallows divided
- 1 cup dry roasted, salted peanuts divided
Instructions
- Preheat oven according to box directions and prepare a 9×9-inch pan as instructed. Mix and bake the brownies as directed. Let cool in the pan for 15–20 minutes.
- In a medium saucepan over medium-low heat, combine the chocolate chips, peanut butter, and butter. Stir until melted and smooth. Remove from heat and let sit for 5 minutes.
- Fold in 2 cups of marshmallows and 3/4 cup of peanuts until evenly combined.
- Spread the topping over the slightly cooled brownies.
- Sprinkle with the remaining 1/2 cup of marshmallows and 1/4 cup of peanuts, pressing gently to help them stick.
- Let cool completely at room temperature, then refrigerate for 2-3 hours before cutting into squares.
Notes
- Refrigerating before slicing helps the topping set, making cutting cleaner.
- Store in an airtight container for up to 3-4 days.
- Wrap individual squares tightly and place in an airtight container or freezer bag. Freeze for up to 3 months.
Nutrition
Disclaimer: Nutrition information is estimated based on automated calculations and should be considered as an approximation. These estimates are provided as a courtesy. Please use your own brand’s nutritional values to verify accuracy.