Smores Brownie Mix Cookies

My neighbor knocked on my door one evening with a wild idea: what if we turned s'mores into a cookie? We were standing in her kitchen at dusk, summer heat still radiating off the counters, when she pulled out a brownie mix box and started laughing about how we could skip the campfire drama entirely. An hour later, we had these chewy brownie cookies topped with marshmallows that were somehow better than the real thing, and honestly, that's when I knew this recipe belonged in regular rotation.

I made these for my daughter's friend group during a sleepover, and watching them pull the cookies apart to see that gooey marshmallow center was worth every second of setup. One kid actually said, 'This is what I'm serving at my wedding someday,' which felt like the ultimate compliment from a 12-year-old.

Ingredients

• 1 box brownie mix (18–20 oz): This is your secret weapon for texture and depth; skip homemade brownie batter and embrace the convenience without sacrificing flavor.
• 2 large eggs: These bind everything together and help the dough hold its shape on the baking sheet.
• 1/3 cup vegetable oil: Oil keeps these cookies impossibly chewy rather than cakey, so don't swap it for butter.
• 1 tablespoon water: Just enough moisture to bring the mix together without making the dough sticky or spreading too much.
• 1/2 cup semi-sweet chocolate chips: Extra chocolate is never wrong, and these dissolve slightly into warm spots throughout the cookie.
• 1/2 cup crushed graham crackers (about 4 sheets): This is where the s'mores magic happens; crush them by hand so you get uneven pieces that add real texture.
• 18 large marshmallows: One per cookie, and they should be fresh because stale marshmallows won't puff properly.
• 1/4 cup mini chocolate chips (optional): A post-bake garnish that catches the light and reminds everyone what they're eating.
• 1/4 cup additional crushed graham crackers (optional): The final texture layer that makes people pause and ask what you did differently.

Instructions

Set the stage:

Preheat your oven to 350°F and line two baking sheets with parchment paper, because removing these cookies without parchment is a heartbreaker.

Mix the base:

Combine the brownie mix, eggs, oil, and water in a large bowl, stirring until just blended and all the dry bits disappear. Don't overmix; you're not making a cake.

Fold in the good stuff:

Gently fold in the chocolate chips and crushed graham crackers with a spatula, keeping the mixture looking rough and textured.

Shape the cookies:

Scoop heaping tablespoons of dough onto your prepared sheets, leaving about 2 inches between each one so they have room to spread slightly without touching.

First bake:

Bake for 8 to 9 minutes, until the edges look set but the centers still jiggle slightly when you gently shake the pan. They'll firm up as they cool, so resist the urge to bake longer.

Top with marshmallows:

Pull the cookies out and immediately press one marshmallow into the center of each while the cookie surface is still warm. Work quickly so the heat melts them slightly into place.

Second bake:

Return to the oven for 1 to 2 minutes, just until the marshmallows puff up and start to look glossy on top.

Toast the tops (the fun part):

If you want golden marshmallows, switch to the broiler for about 30 seconds, but hover near the oven because they go from perfect to charred in a heartbeat. Watch like a hawk.

Garnish immediately:

The moment they come out, while the marshmallow is still tacky, sprinkle mini chocolate chips and extra graham cracker crumbs across the tops so they stick.

Cool and serve:

Let them sit on the baking sheet for 5 minutes to set slightly, then transfer to a wire rack to cool all the way through, though eating one warm with a glass of cold milk is completely acceptable.

Save

There's a specific moment when you pull these cookies out and the kitchen smells like toasted marshmallow mixed with chocolate, and suddenly you understand why people get emotional about food. It's not just dessert; it's summer at your kitchen table.

Why This Beats Traditional S'mores

No need to hunt down sticks, manage open flames, or deal with the awkward geography of campfire seating. These cookies have all the same emotional beats but arrive in your mouth as a unified thing instead of an assembly project where the chocolate never quite melts right. Plus, you can make them on a Tuesday.

Storage and Keeping Them Perfect

Store these in an airtight container at room temperature for up to 3 days, though the marshmallow topping gets slightly firmer as they age. They're still delicious, just less pillowy; if you want that fresh-from-the-oven texture back, warming one in the microwave for 10 seconds works magic.

Ways to Customize and Elevate

Once you nail the basic version, start playing with flavor angles. A pinch of cinnamon in the dough adds unexpected warmth, dark chocolate chips bring deeper richness, and swapping in crushed digestive biscuits instead of graham crackers gives you a completely different vibe. If you have a kitchen torch, skip the broiler step and torch the marshmallows yourself for better control and a more charred, intentional look.

• Try crushing cookies like Thin Mints or Honey Grahams into the dough for a signature twist.
• A tiny sprinkle of sea salt on top of the marshmallow before it sets adds complexity that people will taste but not identify.
• Make these ahead through the first bake, then add marshmallows and finish just before serving for freshest results.

Save

These cookies remind me that the best recipes are the ones that feel like someone solved a problem you didn't know you had. Make them once and you'll understand why my neighbor and I still text about them.

Recipe Questions & Answers

→ What ingredients add the classic smores flavor?

Crushed graham crackers and semi-sweet chocolate chips combined with marshmallow toppings give these cookies their signature smores taste.

→ How do I make sure marshmallows toast evenly?

After baking the cookies, place marshmallows on top and return them to the oven under broil for about 30 seconds, watching closely to prevent burning.

→ Can I substitute dark chocolate for semi-sweet chips?

Yes, using dark chocolate chips enhances the flavor with a richer, slightly bitter taste that pairs well with the marshmallow and graham crackers.

→ What’s the best way to store these cookies?

Store in an airtight container at room temperature for up to three days to maintain freshness and chewy texture.

→ Is it possible to toast marshmallows without broiling?

Yes, a kitchen torch can be used to gently toast the marshmallows for an even golden finish without reheating the whole cookie.