My favorite fudgy brownies topped with marshmallows, peanuts and extra chocolate. These rocky road brownies are chewy, gooey and impossible to resist—arguably even better than rocky road ice cream!
When I was a child, the local grocery sold large trays of rocky road brownies. They were dense and fudgy with a marshmallow layer cloaked in extra chocolate. My parents rarely bought such an indulgence, so those trays became a treasured treat and a warm memory.
There’s something irresistible about a rich chocolate brownie combined with soft marshmallows and salty, crunchy peanuts. Today I’m sharing my homemade version so you can recreate that nostalgic treat at home.
The Perfect Rocky Road Brownies
This brownie base is dense, fudgy and moist without being overly gooey—important when you’re adding sticky marshmallows on top. The recipe combines cocoa powder and melted chocolate for deep chocolate flavor that’s balanced, not cloying. I typically use 50% dark chocolate, but semi‑sweet will work too; you can go up to 70% if you prefer a richer, more bittersweet profile. For this version, 50–60% yields the best balance.
If time is tight, a boxed brownie mix for a 9×13 pan will work. I prefer homemade for these, but you can also use a favorite cocoa-only brownie recipe if that’s your preference.
After the brownies bake and cool, spread a thin layer of chocolate ganache across the top so the marshmallows and peanuts will adhere. Sprinkle mini marshmallows over the ganache and return the pan to the oven just long enough for the marshmallows to puff and soften—only a couple of minutes.
Note: Watch closely when toasting the marshmallows; they can go from puffed to burnt very quickly.
Finish with chopped peanuts and a drizzle of the remaining ganache. The result is everything you want in a rocky road treat: fudgy brownie, gooey marshmallow, salted peanuts and more chocolate. I find these even better than the store-bought trays from my childhood.
If you love rocky road, consider trying other variations like no-bake rocky road pie, bars or fudge for more ways to enjoy the flavor combination.
Rocky Road Brownies
Equipment
-
9×13 Inch Pan
Ingredients
Brownies*
- 1 cup unsalted butter
- 8 oz dark chocolate, finely chopped
- 2 cups white sugar
- 4 large eggs
- 1 cup all-purpose flour
- 1/2 cup cocoa powder
- 1/2 teaspoon salt
Chocolate Ganache
- 8 oz dark chocolate, finely chopped
- 3/4 cup heavy cream
Topping
- 2 cups mini marshmallows
- 1/2 cup chopped peanuts
Instructions
Brownies*
- Preheat the oven to 350°F (180°C). Lightly grease a 9×13 inch pan or line it with parchment paper leaving an overhang.
- Cut the butter into pieces and place it with the chopped chocolate in a large heatproof bowl.
- Melt together—either microwave on medium power in 1-minute bursts, stirring between, until smooth, or melt over a double boiler.
- Let the mixture cool a few minutes, then whisk in the sugar.
- Whisk in the eggs one at a time until incorporated.
- Gently fold in the flour, cocoa powder and salt. If any lumps remain, whisk the batter until smooth.
- Pour the batter into the prepared pan and bake 30–35 minutes, until the top is set and a toothpick comes out clean or with a few moist crumbs. Cool completely.
Ganache & Topping
- Preheat the oven to 375°F (190°C).
- Place the finely chopped chocolate in a heatproof bowl.
- Heat the cream until just below boiling (almost scalding).
- Pour the hot cream over the chocolate and let sit 2–5 minutes, then whisk until smooth. If needed, microwave 30 seconds on medium to fully smooth the ganache.
- Pour about half the ganache over the cooled brownies and spread evenly.
- Sprinkle the mini marshmallows over the ganache layer.
- Return the pan to the oven for 2–4 minutes, just until the marshmallows puff and soften—watch carefully to avoid burning.
- Remove the pan, sprinkle chopped peanuts over the marshmallows, then drizzle with the remaining ganache.
- Let the ganache set, then slice the brownies. If you used parchment, lift the brownies from the pan using the overhang and cut on a board; otherwise, slice in the pan.
Notes
- You can use a boxed brownie mix sized for a 9×13 pan if you prefer. Choose a chewy, moist recipe rather than an overly gooey one for best results.
- Dark chocolate in the 50–70% range works best; semi‑sweet is an acceptable substitute.
- Toasting the marshmallows in the oven is optional but softens and puffs them; if you do toast them, watch closely.
- Store brownies in an airtight container at room temperature up to 4 days, or refrigerate for up to 1 week.
- Nutrition information is an estimate per brownie, assuming 15 even pieces.
Nutrition
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