These S'mores Brownies are exactly what I wanted - gooey brownies with milk chocolate, marshmallows, and graham crackers folded into them from the beginning. No taking the pan out partway through, no toasting marshmallows - simply mix it all together and bake for sweet, almost fall-apart brownies.
S'mores Brownies - at a Glance
- ⏱ Prep Time: 20 minutes
- 🔥 Cook Time: 35 minutes
- ❄️ Cooling Time: 2 hours minimum (overnight recommended)
- ⌛ Total Time: 2 hours 55 minutes (or overnight for best texture)
- 👪 Serves: 30
- 🍽️ Calories: 237
- 🍫 Main Ingredients: Butter, sugar, eggs, flour, cocoa powder, graham crackers, milk chocolate chips, miniature marshmallows.
- 👌 Why You'll Love It: Sweet, gooey s'mores brownies with graham crackers, chocolate chips, and marshmallows baked directly into the batter.
SUMMARIZE & SAVE THIS RECIPE ON
When I took my Girl Scout troop camping, I brainstormed s'mores brownies as a backup plan if our campfire was rained out. Luckily I didn't have to resort to it, but I needed to make it happen later that summer. I came up with a mix-and-bake recipe with s'mores ingredients layered on that needed no babysitting partway through - however, I wasn't happy with the results when I tested them this year, so I reworked the recipe.
Some recipes use just a hint of graham cracker, which gets lost when you bake it; others use a graham cracker crust, which is extra work. I tried layering graham crackers on bottom, but they separated from the brownie layer when I removed them from the pan. I mix in large pieces of broken graham cracker so you can actually tell it's in there.
For these improved s'mores brownies, we fold all of the mix-ins directly into the batter. There's the same volume of mix-ins as there is batter and it seems like they won't all mix in, but they do. Chilling the milk chocolate chips and miniature marshmallows before adding them ensures they don't dissolve and disappear entirely - rather, the marshmallows puff up in the brownies but remain gooey and soft. While you don't get toasted marshmallow from these s'mores, each bite is pillowy and sugary-sweet.
If you love dessert mashups like s'mores + brownies, check out my Chocolate Chip Cookie Cheesecake Bars, which combine the best of both classic desserts, and my Cheesecake Brownies, which have double the cream cheese of most cheesecake brownie recipes.
Why You'll Love These Brownies
These S'mores Brownies are the s'mores dessert of my dreams. Here's why they're amazing.
- 🥄 An easy mix-and-bake method - no layering, no toasting required.
- ☁️ Soft, practically fall-apart gooeyness.
- 🍫 Chilled milk chocolate and chilled miniature marshmallows folded into the batter so they don't disappear into the brownies. Marshmallows puff up and stay gooey.
- 🍪 Lots of graham cracker pieces mixed into the batter so you notice them, but not layered on where they can separate from the bar.
- ✨ So sweet and rich, a little goes a long way - the 9x13 inch pan is perfect when cut into smaller pieces.
Key Ingredients
We make the brownie batter from scratch following my Hershey's Best Brownies recipe, and then fold in store-bought graham crackers, milk chocolate chips, and miniature marshmallows.
Butter: Provides more flavor than oil. Butter also includes water, which I believe helps soften the graham crackers in the batter. Although oil works for brownies in general, I haven't tested it for these.
Cocoa powder: Using cocoa powder is easier than melting chocolate for brownies.
Graham crackers: I use more grahams than other recipes do - around half a box - but even so it's a subtle flavor. Break them into 1-inch pieces so that they're obvious in the brownie, but the batter will be very hard to mix if you leave them larger.
Milk chocolate chips: I considered omitting them since brownies are already chocolate. Semisweet worked fine, but the milk chocolate chips add a sweeter contrast which fits with s'mores. I chill them just as I do for Fudge Brownies.
Miniature marshmallows: I preferred regular marshmallows on top when I originally developed this recipe. Now, however, I use chilled mini marshmallows and stir them into the batter with everything else. Mixing the marshmallows into the batter insulates them slightly from the heat so they puff up, while chilling keeps them from melting entirely into the batter so they stay gooey.
How to Make S'mores Brownies
One: Measure out marshmallows and chocolate chips, and store them in the freezer to chill while you make the batter. Don't skip this step; the brownies aren't as good without chilled marshmallows.
Two: Line a 9x13 inch pan with parchment paper, then spray it with cooking spray. Marshmallows baked into the brownies will make them very soft, and parchment makes a huge difference in being able to remove squares somewhat neatly.
Three: In a very large mixing bowl or pot, melt the butter. Use a whisk to mix in the sugar, eggs, and vanilla once it's cooled enough to not cook the eggs.
Four: Use a rubber spatula to mix in the flour, cocoa powder, baking powder, and salt, just until no dry ingredients remain.
Five: Add the broken graham crackers, milk chocolate chips, and chilled miniature marshmallows.
Six: Bowl will be very full, so carefully scrape the batter from top to bottom over the mix-ins. Fold them in until combined and no large pools of batter remain.
Seven: Scrape batter into parchment-lined pan. Spread it out to the edges, and pat it down as best as possible.
Eight: Bake for 30-35 minutes. The top should look set, and the batter shouldn't wiggle much. Do not overbake. While a toothpick inserted into regular brownies should come out with wet crumbs, a toothpick test isn't reliable here with so much chocolate and marshmallow in the batter.
Nine: Cool completely - at least two hours - before removing the parchment from the pan to cut them. These brownies actually cut best if allowed to sit overnight before cutting.
Cutting, Serving, and Storage
S'mores brownies fall apart and spread out even when completely cooled - it's a matter of how much they fall apart. I've found that brownies cut and removed while warm fall apart more than those allowed to cool overnight; I assume it's because the brownie part hasn't fully set. These are best when made ahead; brownies in the photo below were cut the morning after baking.
Since they're always gooey and fragile, they don't cut into neat squares. I use a bench scraper (affiliate link) to cut down into them, rather than a knife to saw them. If using a knife, press down into the brownie, lift, and press the knife through another section, rather than dragging it through. Use the scraper or a spatula to lift the brownie from the parchment if necessary.
Serve at room temperature - they'll be gooeier and messier in warm weather (thanks, summer). Store in a sealed container; I've seen no difference in chilled versus counter storage. Brownies will still be good after 4 days; I haven't stored them for longer.
S'mores Brownies FAQ
Yes. Oil creates denser brownies. I haven't tested oil in this recipe myself, but I believe the water in the butter helps soften the graham crackers, so s'mores brownies made with oil instead may have a different graham cracker texture.
I think these could easily be made gluten-free if you use gluten-free graham crackers and a gluten-free, cup-for-cup flour blend that includes xanthan gum. Double-check the other ingredients for gluten as well. Gluten-free brownies will likely be a bit more fragile.
So far I haven't had any success substituting other ingredients for eggs in these brownies. I'd recommending searching for a vegan brownie recipe if you need an egg-free option.
🥣 Other Mix-and-Bake Recipes
Some of my favorite recipes are like this one - just mix and bake, with no work afterward. Sure, you have to scoop Monster Cookies, but they're so soft and chewy. And although you roll Gooey Butter Cookies in powdered sugar before baking, they're so sweet and tender that it's worth the extra step.
I hope this becomes a recipe you'll return to. If you try it, a star rating below helps others find it - and I'd love to hear how yours turns out in the comments! 💕 Questions or trouble? Drop a note, and I'll do my best to help.
📖 Recipe
S'mores Brownies
Equipment
- 4 quart pot (or equivalent size mixing bowl)
- wire whisk (affiliate link)
- rubber spatula
- 9x13 inch pan
- parchment paper
Ingredients
Brownie Layer
- 16 tablespoons unsalted butter 227 grams; 2 sticks
- 2 cups sugar 400 grams
- 2 teaspoon vanilla 10 grams
- 4 eggs
- 1 cup all-purpose flour 120 grams
- ¾ cup cocoa powder 60 grams
- ½ teaspoon baking powder
- ¼ teaspoon table salt
Mix-Ins
- 3 cups graham crackers (1 ½ sleeves; 204 grams; broken into 1-inch pieces)
- 1 ½ cups milk chocolate chips (255 grams; 9 ounces)
- 6 cups miniature marshmallows (10 ounce bag; 283 grams)
Instructions
- Place chocolate chips and miniature marshmallows in the freezer to chill before starting.
- Line a 9x13-inch pan (affiliate link) with parchment paper, and spray with cooking spray. Brownies are very delicate after baking; this helps remove them from the pan.
- In a 4 quart pot, melt butter. Use a whisk to stir in sugar and vanilla extract, and whisk in eggs once the mixture is cool enough it won't cook them. Don't overmix.
- Use a rubber spatula to stir in the flour, cocoa powder, baking powder, and salt, breaking up lumps but otherwise mixing only until combined.
- Add the graham cracker pieces, chilled milk chocolate, and chilled mini marshmallows. The pot will be very full. Use the rubber spatula to fold in the mix-ins, scraping the batter from the bottom of the pot. Mix until combined and no puddles of batter remain.
- Spread the batter into the prepared pan, and use the spatula to pat the mixture down; the graham cracker pieces can stick out and create holes otherwise.
- Bake at 350F for 30-35 minutes. Check early if your oven runs hot, and do not overbake. Brownies are done when they don't wiggle much and the top seems set. Testing with a toothpick will not work.
- Cool brownies at least 2 hours before removing from the pan; overnight is better. Cut into 30 squares with a bench scraper (affiliate link) if possible. If using a butter knife, press down through the brownies, lift, then press down through the next section; do not drag the knife. These brownies will not cut neatly.
- Store brownies in an airtight container; room temperature is fine. They should still be moist after 4 days.
Leona Konkel says
I love that I can actually taste the graham crackers when I eat these. They really do disappear quickly - they're hard to resist! I hope you love my recipe as much as I do. If you try it, let me know how it turns out!