Amazing S’mores Cookie Bars: 1 Gooey Treat

September 14, 2025
Written By Maya Thompson

Maya Thompson is the creator, recipe developer, and head cookie taster behind Let's Make Cookies. With a lifelong passion for baking sparked in her grandmother's Midwest kitchen, Maya believes that the best memories are made with a warm cookie in hand. She specializes in creating deliciously simple recipes that any home baker can master. Her mission is to make baking accessible, fun, and a cherished part of everyday life. When she's not covered in a light dusting of flour, you can find her exploring local farmers' markets or sending care packages to her family.

Oh, the smell of a campfire – that gooey, melty magic of s’mores! If you love that classic treat but need something a little more party-friendly, then you absolutely HAVE to try these s’mores cookie bars. They’re basically the s’mores experience you know and love, all squished down into an easy-to-cut bar with that perfect graham cracker crust and an extra dose of chocolatey, marshmallowy goodness. Here at Let’s Make Cookies, we’re all about making those sweet moments simple and shareable, just like my grandma used to do. You can learn more about our Baking Philosophy here! These bars are proof that you don’t need a fire pit to get that amazing campfire flavor!

Why You’ll Love These S’mores Cookie Bars

Seriously, why wouldn’t you love these? They’ve got everything you could ever want in a dessert:

  • Super Easy to Make: You just mix, press, and bake! No fancy techniques needed, which is exactly how I like it.
  • Crowd-Pleaser Guaranteed: Who doesn’t adore s’mores? These bars are always a huge hit at parties, potlucks, or just because you deserve a treat.
  • That Perfect Gooey Texture: We’re talking a chewy cookie base, melty chocolate pockets, and dreamy, gooey marshmallows. It’s pure bliss in every bite!
  • Taste of Nostalgia: They bring back all those cozy campfire memories without all the stickiness and smoke. A total win-win!
  • Perfect for Any Occasion: Whether it’s a casual get-together or a special celebration, these bars fit right in. They’re a fantastic party dessert and an easy potluck dessert option.

Gather Your Ingredients for S’mores Cookie Bars

Alright, let’s get our mise en place ready! The beauty of these s’mores cookie bars is that you probably already have most of this stashed away in your pantry. We’re keeping it simple, just like grandma used to do, with good old reliable ingredients. You know, the kind you can grab at any regular grocery store. No need for a special baking quest!

First up, we need 1 cup (that’s two sticks, by the way) of unsalted butter. Make sure it’s nice and softened, not melted, but soft enough that you can easily make an indent with your finger. Then, we’ll grab 1 cup of granulated sugar and ½ cup of packed light brown sugar. Packing that brown sugar is key for that lovely caramel flavor. You’ll also need 2 large eggs – make sure they’re at room temperature if you can, it helps them mix in better. And don’t forget 1 teaspoon of vanilla extract for that classic warm cookie smell!

For the dry ingredients, we’re looking at 2 ¼ cups of all-purpose flour, 1 teaspoon of baking soda (that’s what gives us a nice lift!), and ½ teaspoon of salt to balance out the sweetness. Now for the star players: 1 ½ cups of graham cracker crumbs – you can buy them already crushed or just crush your own graham crackers in a food processor, super easy! And of course, we need chocolate! I like a mix, so grab 1 cup of milk chocolate chips and 1 cup of chopped semi-sweet chocolate. Finally, the magic touch: 1 cup of mini marshmallows. They’ll get all gooey and wonderful during baking!

Crafting Your Gooey S’mores Cookie Bars: Step-by-Step

Okay, pastry chefs-in-training, let’s get this party started! Making these s’mores cookie bars is honestly so straightforward, you’ll wonder why you haven’t done it sooner. It’s all about layering those classic campfire flavors into one perfectly baked treat. Trust me, the payoff is HUGE!

Preparing the Pan and Dough Base

First things first, let’s get the oven preheating to 350°F (175°C) because a hot oven is happy oven! Grab your trusty 9×13 inch baking pan and give it a good grease and flour – we want these bars to slide out like a dream later. In your biggest mixing bowl, cream together that softened butter, granulated sugar, and packed brown sugar until it’s light and fluffy. Think sunshine yellow and airy! Then, beat in your eggs one at a time, followed by that splash of vanilla extract. In a separate bowl, whisk together your flour, baking soda, and salt – this just makes sure everything is evenly distributed.

Adding the S’mores Elements

Now for the cookie dough magic! Gradually add those dry ingredients to your wet mixture, mixing until it’s just combined. Don’t overmix, or you’ll end up with tough bars, and nobody wants that! Next, stir in the graham cracker crumbs – this is what gives us that signature crusty sweetness. Then, fold in those milk chocolate chips and chopped semi-sweet chocolate. Oh yeah, get all those yummy chocolate pockets in there! Take about half of this glorious cookie dough and press it evenly into the bottom of your prepared pan. This forms the base for our s’mores masterpiece! If you love a good cookie base, you should totally check out my homemade chocolate chip cookie recipe for inspiration!

Layering Marshmallows and Finishing the Dough

This is where it gets really exciting! Sprinkle those mini marshmallows evenly all over the dough base you just pressed into the pan. Try to get them as close to the edges as possible for maximum gooeyness in every bite. Now, take the remaining half of your cookie dough and gently dollop it over the marshmallows. You can use your hands or a spatula to gently spread it out, covering as much of the marshmallow layer as you can. It doesn’t have to be perfect; a little peek-a-boo marshmallow is totally fine!

Baking and Cooling for Perfect S’mores Cookie Bars

Pop that pan into the preheated oven and let it bake for about 25 to 30 minutes. You’re looking for those edges to turn a lovely golden brown, and the center should look mostly set. It’ll continue to firm up as it cools. This is a crucial step for those clean slices you want for your party dessert or potluck! Let those bars cool COMPLETELY in the pan before you even THINK about cutting them. Seriously, patience is key here for that perfect sheet pan dessert.

Tips for Perfectly Sliced S’mores Cookie Bars

Okay, so you’ve baked these gorgeous s’mores cookie bars, and you’re tempted to dive right in, right? I totally get it! But for those super clean cuts you want for your party dessert or potluck, a little patience goes a long way. My best trick, and one I swear by for flawless slicing, is to pop the pan into the fridge for about 30 minutes after it’s cooled down a bit. Chilling firms everything up beautifully, especially those marshmallows and chocolate, making it so much easier to get sharp edges. It’s a game-changer, trust me!

Looking to spice things up a bit? Feel free to play with your chocolate! Dark chocolate chips add a lovely richness, or maybe some white chocolate for a different vibe? And if you really want to amp up that campfire dessert feel, you can carefully pop the whole pan under the broiler for just a minute or two at the end of baking. Keep a super close eye on it – you want those marshmallows just lightly toasted, not burnt! This whole recipe is about capturing that s’mores magic, and these little tweaks just make them even more special.

Storing and Reheating Your S’mores Cookie Bars

These s’mores cookie bars are fantastic as make-ahead bars, which is always a win when you’re prepping for a party or just want a treat ready to go. Once they’ve completely cooled (seriously, don’t skip that cooling step!), you can store them in an airtight container right on the counter. They’ll stay wonderfully fresh and gooey for about 3 days. My pantry usually has a dedicated spot for these, just in case!

Now, if by some miracle you have leftovers after that, or you just prefer them a *tad* warmer, you can totally reheat them. Pop a bar onto a microwave-safe plate for about 10-15 seconds. Just enough to soften those melty chocolate bits and marshmallows again. Be careful though, they can get hot super fast! They’re also delicious at room temp, so no pressure if reheating isn’t your jam. They’re pretty perfect any way you slice ’em (pun intended!).

Frequently Asked Questions About S’mores Cookie Bars

Got questions about these amazing s’mores cookie bars? I’ve got answers! This is one of those recipes that seems straightforward, but sometimes little things pop into your head, and that’s totally normal. We want these easy dessert bars to be perfect for you every single time, whether you’re whipping them up for a party or just because! These simple bar cookies are so forgiving, but here are some common things people ask:

Can I use different types of chocolate?

Oh, absolutely! That’s the fun part. While milk and semi-sweet chocolate chips are my go-to for a classic s’mores vibe, feel free to mix it up. Dark chocolate chips will give you a richer, more intense chocolate flavor, and white chocolate chips add a lovely creamy sweetness. You could even chop up a good quality chocolate bar if you have one lying around! Just remember, the type of chocolate you use will change the overall flavor profile a little, but it’ll still be SO delicious!

How do I get the gooey marshmallow texture?

The secret to that dreamy, gooey marshmallow texture is definitely using mini marshmallows and spreading them out evenly. They’re small enough to create a lovely melt throughout the bars when they bake. For an extra campfire touch, you can always pop them under the broiler for a minute or two at the very end – just watch them like a hawk because they can go from perfectly toasted to burnt in a flash! That melty marshmallow is what makes them such a delightful gooey dessert.

Are these good for back to school treats?

Are they ever! These s’mores cookie bars are perfect for back to school treats. They pack up so easily in lunchboxes for a sweet surprise, and kids absolutely adore them. Plus, since they’re make-ahead bars, you can have them ready to go for busy mornings. They definitely add a little bit of sunshine to a school day, making them a fantastic family dessert, too! If you’re looking for other fun treats, you might like my easy snickerdoodle cookies!

Estimated Nutritional Information

Now, I always like to give you a rough idea of what you’re getting into with these little squares of joy. Keep in mind, these numbers are just estimates, and they can totally change depending on the exact brands you use or if you decide to add extra chocolate chips (guilty!). But generally, each one of these delicious s’mores cookie bars comes in around 250 calories. You’ll also find about 13g of fat, 3g of protein, 30g of carbs, and 25g of sugar. It’s a treat, right? Enjoy!

Share Your S’mores Cookie Bar Creations!

Alright, bakers! I truly hope you have as much fun making and devouring these s’mores cookie bars as I do. If you whip up a batch, please, pretty please, leave a comment below and let me know what you think! I love hearing your feedback and seeing your creations. Don’t forget to share photos of your gooey masterpieces on social media – tag me so I can see your amazing work! If you have any other questions or want to share your own tips, you can always reach out!

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Gooey S’mores Cookie Bars

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Easy s’mores cookie bars with a graham cracker crust, gooey marshmallow, and rich chocolate. Perfect for parties and potlucks.

  • Author: maya
  • Prep Time: 20 min
  • Cook Time: 30 min
  • Total Time: 50 min
  • Yield: 24 bars 1x
  • Category: Dessert
  • Method: Baking
  • Cuisine: American
  • Diet: Vegetarian

Ingredients

Scale
  • 1 cup (2 sticks) unsalted butter, softened
  • 1 cup granulated sugar
  • 1/2 cup packed light brown sugar
  • 2 large eggs
  • 1 teaspoon vanilla extract
  • 2 1/4 cups all-purpose flour
  • 1 teaspoon baking soda
  • 1/2 teaspoon salt
  • 1 1/2 cups graham cracker crumbs
  • 1 cup milk chocolate chips
  • 1 cup chopped semi-sweet chocolate
  • 1 cup mini marshmallows

Instructions

  1. Preheat your oven to 350°F (175°C). Grease and flour a 9×13 inch baking pan.
  2. In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
  3. Beat in the eggs one at a time, then stir in the vanilla extract.
  4. In a separate bowl, whisk together the flour, baking soda, and salt.
  5. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
  6. Stir in the graham cracker crumbs, milk chocolate chips, and chopped semi-sweet chocolate.
  7. Press half of the cookie dough evenly into the bottom of the prepared baking pan.
  8. Sprinkle the mini marshmallows evenly over the dough.
  9. Dollop the remaining cookie dough over the marshmallows, spreading it gently to cover.
  10. Bake for 25-30 minutes, or until the edges are golden brown and the center is set.
  11. Let the bars cool completely in the pan before cutting into squares.

Notes

  • For cleaner slices, chill the bars in the refrigerator for at least 30 minutes before cutting.
  • Add different types of chocolate like dark chocolate or white chocolate for variation.
  • You can toast the marshmallows slightly under the broiler for a campfire flavor, but watch them closely to prevent burning.
  • These bars can be made ahead and stored in an airtight container at room temperature for up to 3 days.

Nutrition

  • Serving Size: 1 bar
  • Calories: 250
  • Sugar: 25g
  • Sodium: 150mg
  • Fat: 13g
  • Saturated Fat: 8g
  • Unsaturated Fat: 5g
  • Trans Fat: 0g
  • Carbohydrates: 30g
  • Fiber: 1g
  • Protein: 3g
  • Cholesterol: 40mg

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