S’mores Brownie Marshmallow Bars

Featured in: Creative Sweet Treats

S’mores Brownie Marshmallow Bars combine classic chocolate brownies with the flavors of campfire s’mores. Fudgy brownies are layered with fluffy marshmallows and crunchy graham cracker crumbs, then baked until gooey and golden. The chocolate base stays moist while the topping melts for a deliciously chewy bite with a crisp finish. These bars are perfect for gatherings and offer an irresistible blend of chocolate and toasted marshmallow, reminiscent of classic s’mores in every slice.

Updated on Sun, 26 Oct 2025 14:59:59 GMT
Gooey S’mores Brownie Bars recipe close-up: melted marshmallows and graham cracker perfection. Pin it
Gooey S’mores Brownie Bars recipe close-up: melted marshmallows and graham cracker perfection. | fungeniusrecipe.com

These S’mores Brownie Bars are the ultimate answer to every craving for campfire nostalgia with a decadent twist. Imagine deeply fudgy brownies layered with melty marshmallows and a buttery, golden graham cracker topping: each bite melts in your mouth while still holding a hint of summer. These bars are perfect for backyard parties, potlucks, or cozy nights in when you want all the fun of s’mores without the mess.

I love to watch my kids crowd around the baking pan after dinner, eagerly waiting for the marshmallows to bubble and toast under the broiler. The first time I brought these to a family barbecue, there was not a crumb left by the end of the night.

Ingredients

  • Butter: Adds richness and chewiness to the brownie base Use high-quality unsalted butter for the best flavor
  • Bittersweet chocolate: Deepens the chocolate flavor Look for bars with around seventy percent cocoa content
  • Sugar: Gives that classic brownie sweetness and fudgy texture Opt for fine granulated sugar for smooth blending
  • Eggs: Bind everything together and give shine to the top Choose fresh large eggs
  • Vanilla extract: Rounds out all the flavors Pure vanilla works best here
  • All-purpose flour: Creates structure in the brownies Measure flour by spooning it gently into your cup for best results
  • Cocoa powder: Boosts the chocolate intensity Go for Dutch process if possible for a deeper cocoa flavor
  • Salt: Balances out the sweetness and enhances all the flavors Fine sea salt makes a difference
  • Graham crackers: Add that signature s’mores crunch and flavor Choose fresh crackers and give them a quick crush for texture
  • Mini marshmallows: Melt and toast just like at the campfire Fresh marshmallows work best for even browning

Instructions

Make the Brownie Batter:
Melt butter and chopped bittersweet chocolate together in a large microwave-safe bowl or over a double boiler Stir until completely smooth and glossy Let cool slightly then whisk in sugar followed by eggs one at a time until the mixture is shiny and cohesive Finally, stir in vanilla extract
Combine the Dry Ingredients:
In a separate bowl whisk together flour cocoa powder and salt This step helps evenly distribute the cocoa and prevent lumps
Mix and Pour:
Add the dry ingredients to the wet ingredients Fold together gently just until you see no more streaks of flour Overmixing can make brownies tough
Bake the Brownies:
Pour the batter into a parchment-lined baking pan and smooth the top with a spatula Bake at three hundred fifty degrees Fahrenheit for about twenty-five minutes The edges should seem set but the center still looks slightly moist
Add the Marshmallows and Graham Crackers:
Sprinkle a generous layer of mini marshmallows and crushed graham crackers evenly over the hot brownies Return to the oven Bake for another seven minutes until the marshmallows are puffed up and lightly golden
Finish with a Toast:
Switch the oven to broil for thirty seconds to one minute Watch closely so the marshmallows get deeply golden but do not burn Let the bars cool before slicing for clean edges
Golden, toasted marshmallow topping on homemade S'mores Brownie Bars recipe, ready to slice. Pin it
Golden, toasted marshmallow topping on homemade S'mores Brownie Bars recipe, ready to slice. | fungeniusrecipe.com

My favorite part is that smoky hint you get when broiling the marshmallows at the very end. The first time my daughter helped sprinkle the grahams, she was so proud seeing her creation bubbling under the broiler.

Storage Tips

Once cooled completely, store these bars in an airtight container at room temperature for up to three days. They keep their fudgy texture best when stored in a single layer. For longer storage, pop them in the fridge or wrap tightly and freeze for up to a month. I like to reheat individual bars in the microwave for ten seconds to bring back that gooey marshmallow top.

Ingredient Substitutions

If you do not have bittersweet chocolate, you can use semi-sweet chocolate chips in a pinch. Swap out mini marshmallows for large ones cut into pieces: they melt just as beautifully. For a gluten-free option, substitute gluten-free graham crackers and flour.

Serving Suggestions

These S’mores Brownie Bars shine at summer picnics with cold milk or hot cocoa. Serve them warm for a true gooey experience, or chill in the fridge for firmer, portable treats that are perfect for lunchboxes or road trips. For a twist, drizzle melted chocolate over the top or add chopped nuts for crunch.

Cultural and Historical Context

S’mores have been a fireside favorite since the nineteen twenties, beloved by generations for the magic of toasted marshmallow and chocolate. Marrying them with brownies brings all that joy into the kitchen, no campfire required. Brownies themselves are an American classic, so this recipe is a true meeting of nostalgia and innovation.

Seasonal Adaptations

Use peppermint marshmallows in winter for a festive twist Top with pastel-colored marshmallows for spring parties Replace graham crackers with gingersnaps in fall for extra spice

Success Stories

Friends always ask for the recipe after tasting these at potlucks: they are so much easier than making s’mores for a crowd. My kids even brought them to a bake sale, and they sold out in less than fifteen minutes. Several readers have shared photos of their golden-bubbled bars, and I never get tired of seeing those marshmallowy smiles.

Freezer Meal Conversion

Brownie bars freeze beautifully. Bake fully, cool, then wrap tightly in plastic and foil before freezing. Defrost at room temperature or microwave for that fresh-from-the-oven marshmallow effect. Careful not to freeze with too many add-ons on top or they might get sticky.

Warm, decadent S’mores Brownie Bars recipe invitingly displayed; the perfect summer dessert. Pin it
Warm, decadent S’mores Brownie Bars recipe invitingly displayed; the perfect summer dessert. | fungeniusrecipe.com

Make these S’mores Brownie Bars for your next gathering and see everyone smile. Satisfy nostalgia and dessert cravings in every baked square.

Recipe FAQs

How do I prevent brownies from overbaking?

Keep an eye on the baking time and use a toothpick to check for moist crumbs, not a dry center. Remove from oven as soon as edges set.

Can I use mini marshmallows?

Yes, mini marshmallows melt quickly and distribute evenly across the brownie surface for a gooey topping.

Should graham crackers be crushed?

Crush graham crackers into coarse crumbs. Sprinkle over marshmallows for extra texture and flavor.

Do these bars store well?

Store in an airtight container at room temperature for up to three days. They remain chewy and flavorful.

Can I add chocolate chips?

Chocolate chips can be mixed into batter or sprinkled on top for extra richness and texture.

S’mores Brownie Marshmallow Bars

Fudgy brownies layered with marshmallows and graham cracker crumbs, baked until golden and gooey.

Prep time
20 minutes
Cook time
35 minutes
Complete time
55 minutes
Created by Fungeniusrecipe Chloe Anderson

Recipe category Creative Sweet Treats

Skill level Medium

Cuisine type American

Portions 16 Number of servings

Dietary details Meatless

What You Need

Brownie Base

01 1 cup unsalted butter, melted
02 2 cups granulated sugar
03 4 large eggs
04 1 teaspoon vanilla extract
05 1 cup all-purpose flour
06 1 cup unsweetened cocoa powder
07 0.5 teaspoon salt

Toppings

01 2 cups mini marshmallows
02 1 cup graham cracker crumbs
03 0.5 cup semi-sweet chocolate chips

How to Make

Step 01

Preheat Oven: Set oven to 350°F (175°C). Prepare a 9x13 inch baking pan by lining with parchment paper.

Step 02

Combine Wet Ingredients: Whisk melted butter and sugar in a large mixing bowl until well blended. Add eggs one at a time, mixing thoroughly after each addition. Stir in vanilla extract.

Step 03

Incorporate Dry Ingredients: Sift together flour, cocoa powder, and salt in a separate bowl. Gradually fold dry mixture into wet ingredients until a smooth batter forms.

Step 04

Transfer to Pan: Pour brownie batter evenly into the prepared pan and smooth the surface with a spatula.

Step 05

Bake Brownie Layer: Place pan in the oven and bake for 25 minutes, until edges are set but center is slightly soft.

Step 06

Add S’mores Toppings: Remove pan from oven. Sprinkle mini marshmallows, graham cracker crumbs, and chocolate chips evenly over the brownie layer.

Step 07

Finish Baking: Return pan to oven and bake for an additional 8 to 10 minutes, until marshmallows are golden and chocolate chips have begun to melt.

Step 08

Cool and Portion: Allow bars to cool in pan for at least 30 minutes. Lift from pan using parchment paper and cut into squares.

Equipment needed

  • 9x13 inch baking pan
  • Parchment paper
  • Mixing bowls
  • Whisk
  • Spatula

Allergy details

Don’t forget to check each item for allergens. Talk to a healthcare professional if you’re unsure.
  • Contains eggs, wheat, and dairy.

Nutrition (each serving)

These nutrition facts are for reference only. Always consult an expert for medical advice.
  • Calorie count: 310
  • Fat content: 13 g
  • Carbohydrates: 46 g
  • Protein content: 3 g