Why choose between s’mores and brownies when you can have both? These S’mores Brownies have a graham cracker crust, the fudgiest brownie layer, and toasted marshmallows and chocolate piled on top!

If you’ve been following Bunsen Burner Bakery for any length of time, you know how much I love s’mores-themed desserts.  

(Real talk: I like s’mores-ish desserts more than actual s’mores.  I hate how the graham cracker always breaks and crumbles when you try to bite into it…)

National S’mores Day, which is the only silly food holiday I acknowledge, is August 10th.  So every August, I share a new s’mores dessert.

Brownie of the Month + National S’mores Day = S’mores Brownies.  Obviously!

There are dozens of variations on s’mores brownies, but my favorite version includes a graham cracker crust and a thick, fudgy chocolate brownie middle, topped with a combination of toasted miniature marshmallows, chopped milk chocolate, and more graham cracker pieces.

It’s the best parts of a brownie (fudgy, chocolatey) combined with the best parts of a s’more (gooey marshmallows and melted chocolate).

This, my friends, is summer in a brownie.  But because it’s toasted in your oven, you can enjoy it all year long.

Graham Cracker Crust

Making the crust is as simple as grinding the graham crackers into crumbs.  This can be done using a food processor, blender, or smashing the graham crackers with a rolling pin or heavy pan. 

Just make sure the crumbs are finely ground and uniform in size!

Then mix in some butter, a little extra sugar (the sugar crystals help bind the butter to the graham cracker crumbs), and press into the bottom of the pan. 

Bake until just slightly browned and pour in the brownie batter.

Thick Fudgy Brownies

These s’mores brownies use my go-to fudgy brownie recipe when I’m looking for soft brownies without any mix-ins.  

You’ll see this recipe calls for Dutch processed cocoa powder – what does this mean, and is it really necessary?  It’s time for my favorite subject… kitchen chemistry!

Kitchen Chemistry

Cocoa beans are naturally fairly acidic, with a pH of 5.5.  When cocoa beans are Dutched, they are washed with potassium to neutralizes the acidity.  (Inversely, natural cocoa powder is made from roasted and ground beans, and thus remains acidic.) Dutch processed cocoa powder has a much smoother, more mellow flavor than acidic natural cocoa powder.

So now that we know the difference, the next step is understanding if you can switch back and forth between the two.

Dutch-processed cocoa powder has a neutral pH, which means it pairs with baking powder as a chemical leavener.  Cakes made with natural unsweetened cocoa powder, however, generally call for baking soda, because the ingredients are already acidic.

But in this brownie recipe, we don’t use baking soda OR baking powder, which means you can use whichever you’d like! 

Dutch-processed cocoa will result in a smoother chocolate taste and slightly darker brownies, but you can feel free to switch in this recipe, based on what you have on hand.

Toasted Marshmallow Topping

After the brownies bake, top them with crumbled graham crackers, chopped milk chocolate bars, and of course – miniature marshmallows!  

The easiest way to toast your marshmallows indoors is to use the broiler of your oven.  Place the pan 8-ish inches below the broiler and watch closely!  Marshmallows go from toasty to burnt very quickly.

Then let the brownies (and marshmallows!) cool before slicing; slicing warm brownies will result in crumbly brownies and extra gooey marshmallows that stick to the knife!

Recommended Tools for S’mores Brownies

• 9″ Square Baking Pan: A metal baking pan conducts heat better than glass or ceramic.
• Parchment Paper: The brownies will release better from a parchment paper-lined baking pan than from aluminum foil or greasing the pan.
• Mixing Bowls: My favorite set of microwave and dishwasher-safe glass mixing bowls!
• Dutch Process Cocoa Powder: Brownies are only as good as the cocoa powder they’re made with – use the good quality stuff!
• Kitchen Torch: While the broiler from your oven works, a culinary torch provides a little more control when it comes to toasting the marshmallows.

Tips and Tricks for the Best S’mores Brownies

1. Line the pan with parchment paper.  The slightly melted marshmallows will release from parchment paper easier than from aluminum foil or a greased pan.
2. Either natural unsweetened or Dutch-process cocoa powder can be used.  I suggest using Dutch-process cocoa powder; the color is darker and richer and the cocoa flavor is more prominent.
3. Use good quality cocoa powder for the best chocolate flavor.  My favorite brands include Cacao Barry Extra Brute, Droste, and Valhrona.
4. Use miniature marshmallows for the topping – or cut full-sized marshmallows into smaller pieces.  Jumbo marshmallows will burn on the outside without melting on the inside.
5. Need more s’mores brownies? (Yes!) Double the recipe and bake in a 9×13-inch pan, adding an extra 5 minutes to the baking time.

More S’mores Recipes

• S’mores Quick Bread
• S’mores  Cookie Cake
• Gooey S’mores Bars
• S’mores Pie
• Three Layer S’mores Cake
• S’mores Cheesecake
• S’mores Babka

2020 Brownie of the Month Series