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S'mores Bars are a decadent, layered oven-baked dessert (similar to cookie sandwiches) inspired by classic summer campfire s'mores. These cookie bars feature a fudgy brownie base, gooey marshmallow creme center, and a soft, golden cookie layer on top. Topped with extra chocolate chips, graham cracker chunks, and toasted mini marshmallows.
Make These S'mores Bars and Watch Them Vanish!
Soft and gooey S'mores Cookie Bars are always everyone's favorite treat at summer cookouts, BBQs, and parties-they disappear fast every time I make them (along with my raspberry brownies and lemon brownies)! They're perfect for family gatherings, school parties, cozy winter baking, or even a fun dessert for a movie night. Kid- and adult-approved. These are also great for gifting-just wrap them up once cooled!
Obsessed: Why These S'mores Bars Steal the Show
- Three Desserts in One: This isn't just a brownie or a cookie bar-it's got everything! Brownie base, marshmallow middle, cookie top, all with that classic s'mores combo.
- No Campfire Required: You get all the nostalgic s'mores vibes without having to find a stick or deal with bugs. Just pop these in the oven!
- Super Gooey & Soft: I specifically keep the centers soft, gooey, and a little messy (just like s'mores are meant to be). I do not overbake, and I recommend you don't either!
- Customizable & Fun: Add peanut butter cups, toffee bits, Biscoff cookies, swap out chocolate chips, or use flavored graham crackers. I've tried it all-delicious every way. My other favorite summer bar desserts are strawberry crumble bars, seven layer bars, and apple squares.
Main Ingredients & Helpful Substitutions
- Betty Crocker Cookie Brownie Mix: The base of the bars. If you don't have this specific mix, any similar cookie brownie mix (about 17-18 oz) will work.
- Unsalted Butter: I always use unsalted to control the saltiness. In a pinch, salted butter works-just reduce added salt slightly.
- Egg + Egg Yolk: The extra yolk keeps the brownie layer extra fudgy and rich.
- Heavy Whipping Cream: This is my secret for ultra-soft, chewy layers! You can swap with half-and-half if you must, but cream is best.
- Marshmallow Creme: This gives you that sticky, gooey s'mores center without making a mess. Regular marshmallows will not layer the same.
- Graham Crackers: Classic! I love them roughly chopped for texture. Try cinnamon or chocolate graham crackers for a different flavor.
- Semi-Sweet Chocolate Chips: Balance the sweetness, but use milk or dark chocolate chips if you prefer.
- Light Brown Sugar & Vanilla Bean Paste: Brown sugar adds sweetness and softness; vanilla bean paste adds an intense, real vanilla flavor. No paste? Regular vanilla extract is just fine.
- Mini Marshmallows: They work great as a topping for these cookie bars! These toast beautifully under the broiler at the end.
- Flakey Sea Salt (optional): If you're a salty-sweet fan, this is chef's kiss on top!
Tips for Success
- Don't Overbake: The centers of the cookie bars should look just barely set. They'll finish setting as they cool-trust the process!
- Spread Marshmallow Carefully: Marshmallow creme is sticky-work slowly, and don't stress if it's not perfect. Gaps make gooey pockets!
- Broil for Toasted Tops: Want golden, toasty marshmallows? Broil the pan for 1-2 minutes after baking-just watch closely so nothing burns.
- Chill before Slicing: If you want super clean bar edges, let the pan cool completely, then chill briefly before cutting into the gooey S'mores bars.
S'mores Bars
S'mores Bars are a decadent, layered oven-baked dessert (similar to cookie sandwiches) inspired by classic summer campfire s'mores. These cookie bars feature a fudgy brownie base, gooey marshmallow creme center, and a soft, golden cookie layer on top. Topped with extra chocolate chips, graham cracker chunks, and toasted mini marshmallows.
Ingredients
Brownie Layer:
- 17.4 ounces box of Betty Crocker Cookie Brownie Mix
- 6 tablespoons unsalted butter melted
- 1 large egg at room temperature
- 1 egg yolk at room temperature
- 2 tablespoons heavy whipping cream at room temperature
- ⅛ teaspoon salt
Marshmallow Creme Layer:
- 1 cup marshmallow creme
- ½ cup semi-sweet chocolate chips
- 1 cup rough chopped graham crackers
Cookie Layer:
- 4 tablespoons all-purpose flour
- 2 tablespoons heavy whipping cream at room temperature
- ¼ cup unsalted butter softened to room temperature
- ¼ cup light brown sugar firmly packed
- 1 tablespoon vanilla bean paste
- ⅛ teaspoon salt
Toppings:
- ½ cup semi-sweet chocolate chips
- ½ cup rough chopped graham crackers
- ½ cup mini marshmallows
Optional Garnish:
- Flakey Sea Salt
Instructions
- The first step is to place one of the oven racks in in the center of the oven and preheat the oven to 325˚ degrees Fahrenheit.
- Use nonstick cooking spray to evenly coat an 8x8 baking pan, and then line the pan with parchment paper. This step helps you to easily remove the bars from the pan after baking.
Prepare the brownie layer:
- Use a microwave safe bowl or dish and melt 6 tablespoons of unsalted butter for the brownie mix. Once the butter is melted, pour it into a large mixing bowl and allow it to cool for a few minutes.
- Once the butter has cooled slightly, add in the brownie mix, and stir until combined. Next you will stir in 2 tablespoons of heavy whipping cream and ⅛ teaspoon of salt. Once everything is mixed in, add the egg and egg yolk, and stir until everything is fully mixed.
- Pour the brownie mixture into the prepared 8x8 pan and spread it out evenly using a spatula.
Add marshmallow creme and chocolate chip layers:
- Next you will spread the 1 cup of marshmallow creme evenly on top of the brownie layer. I like to keep the creme just slightly away from the edges of the edges of the pan. Start by putting the marshmallow creme in the center of the pan and spread it out to the sides. The marshmallow creme is sticky to work with, so take your time spreading it into an even layer.
- Sprinkle ½ cup of semi-sweet chocolate chips on top of the marshmallow creme layer, followed by 1 cup of the rough chopped graham cracker pieces.
Prepare the cookie layer:
- In a clean mixing bowl add the cookie mix, 4 tablespoons of all-purpose flour, 2 tablespoons of heavy whipping cream, ¼ cup of softened room temperature butter, ¼ cup light brown sugar, 1 tablespoon of vanilla bean paste, and ⅛ teaspoon of salt, and stir until everything is combined. The cookie dough will be thick and firm.
- Divide the cookie dough into 4-5 balls and press them in your hand to flatten them out and place them on top of the marshmallow creme layer. Make sure you can still see some of the marshmallow creme below.
Bake:
- Bake the s'mores bars at 325˚ Fahrenheit for approximately 40-50 minutes. Oven times do vary, so be sure to insert a toothpick or knife in the center of the pan to check the bars and ensure they are done. You want to make sure not to overbake the bars, they should still be soft. The bars will continue to set up as they cool, and they taste best when they are soft and gooey!
- Once you determine the s'mores bars are done baking, remove the pan from the oven and transfer it to a wire rack to cool to room temperature. While the bars are still warm, press into the top ½ cup of chocolate chips, the ½ cup of rough chopped graham crackers and ½ cup mini marshmallows. Next, as an optional garnish, sprinkle the bars lightly with flakey sea salt on top.
- Once the bars have cooled to room temperature, use the parchment paper to lift them from the pan and cut the bars evenly into 16 pieces.
Notes
- How to brown the mini marshmallows on top of the cookie bars? I recommend you do the following: after you add the chocolate chips, graham cracker pieces and mini marshmallows to the top of the baked bars, put the pan back in the oven on the middle rack and turn the broiler on for 1-2 minutes. Be sure to watch the pan, you only want to lightly brown the mini marshmallows on top, you don't want them to start melting.
- Notes about vanilla: If you don't want to use vanilla bean paste in the recipe or if you don't have it, feel free to use equal parts vanilla extract. When using vanilla bean paste, I personally do not recommend using bourbon vanilla bean paste because it can alter the flavor of the recipe ever so slightly.
- Variations - other chopped candy bars: Feel free to add your favorite chopped candy bar or candy pieces to this recipe. I love adding chopped up pieces of Reese's Peanut Butter Cups! You can also try toffee bits, or even Biscoff cookies work well. I recommend customizing each batch and experimenting.
- Storage instructions: The s'mores bars should be stored covered in an airtight container and they should last up to 5 days.
You will need the following supplies:
- 8x8 Baking Pan
- Parchment Paper
- Measuring Cups
- Mixing Bowls
- Measuring Spoons
- Rubber Spatula
Nutrition Disclaimer:
The nutritional information on this website is only an estimate and is provided for convenience and as a courtesy only. The accuracy of the nutritional information for any recipe on this site is not guaranteed. It should not be used as a substitute for a professional nutritionist's advice.
How to Make S'mores Bars (Step-by-Step)
- Preheat your oven to 325°F and set a rack in the center. Coat an 8x8 pan with nonstick spray and line it with parchment.
- Make the brownie layer: melt the butter, let it cool slightly, then mix in the brownie mix, cream, salt, egg, and yolk until smooth. Spread this into your prepared pan.
- Add more layers: Next, gently spread the marshmallow creme over the brownie layer (it's sticky-just do your best!), then sprinkle on chocolate chips and graham cracker pieces.
- Make the cookie layer: stir together the cookie mix, flour, cream, softened butter, brown sugar, vanilla bean paste, and salt until a thick dough forms.
- Add the cookie layer: Flatten pieces of dough in your hands and arrange them over the marshmallow layer, leaving some marshmallow showing through.
- Bake for 40-50 minutes, until the bars are just set but still soft-don't overbake! Cool the pan on a wire rack.
- Add toppings: While still warm, press extra chocolate chips, more graham crackers, and mini marshmallows on top, plus a sprinkle of flakey sea salt if you like.
- Broil for 1 or 2 minutes to brown the marshmallows if you like
- Slice: Once completely cool, lift out and cut into 16 bars.
I hate to buy whipping cream and half-and-half when I'm going to use such a small amouunt. Is there a swap I could make?
Hi Judy! You can swap in whole milk or even 2% milk instead. The texture might be slightly less rich, but they’ll still turn out gooey and delicious!
These were the best thing ever! I made them at the cabin last weekend for my kids and their friends. Not a single slice left! My kids loved it and they hate burnt marshmallows so these worked perfectly as they were not burnt.
Thank you, Savanah, for trying this recipe and leaving a review - I so appreciate it! ❤️