These Fudgy S'mores Brownies combine all the best flavours of campfire treats. A crunchy biscuit base is topped with a fudgy, decadent brownie layer and finished off with a gooey, toasted marshmallow layer. This is the ultimate treat!
My household loves brownies with a passion. They make the perfect snack, dessert or bring along a treat to a party. My Chocolate Cherrie Brownies and Small-Batch Salted Caramel Brownies always go down a treat. And I also have a delicious Raspberry White Chocolate Brownie recipe in my Small Batch Desserts E-book when you subscribe.
As a family, we aren't campers. And I know that toasting marshmallows over an open fire and squishing them with chocolate between two crackers, is a quintessential part of camping. Well, I don't want to miss out on all the fun, so set about getting all those campfire flavours at home.
These Fudgy S'mores Brownies hit all the s'mores cravings. Fudgy, rich brownie layer sandwiched between a crunchy biscuit layer and gooey, toasted marshmallow layer on the top. Every component compliments the other and works perfectly. Close your eyes and you'll be sat in the woods next to a roaring fire pit!
Why you'll love this recipe
- Decadent. Rich, fudgy, luscious and chocolatey! These brownies have it all in one bite.
- Two desserts in one. Can't decide what to go for...this is the perfect mix up of your favourite toasty s'mores and delicious brownies.
- Make ahead. Take all the pressure off and make the biscuit base and brownie layer ahead of time. When ready to serve, simply layer on the marshmallow fluff and toast the top. Ready to go in five minutes!
Ingredients needed
If we're replicating the flavours of s'more, what exactly are they? S’mores are a toasted marshmallow and a square of chocolate sandwiched between two graham crackers. The first published recipe was by the Girl Scouts in the US in 1927 and here they documented the toasting of the marshmallow in a campfire before constructing the s’mores. Head on over for more little known S’mores facts over on Real Simple.
All the ingredients in this layered s'mores brownies recipe are standard store cupboard ingredients. I'll give you options where I can so that you can whip this together in no time without the fuss of having to visit the store.
Step-by-step instructions
*Be sure to see the recipe card below for the full ingredients list & instructions!*
As mentioned, to re-create the s'mores flavours, we need the three elements, the graham cracker, chocolate bar and marshmallow layers, but we need to turn them into dessert form. So a biscuit layer crust, like a cheesecake, is baked with the fudgy, uber chocolatey brownies layer on top. To get the ultimate toasty marshmallow layer, we recreate the toasty flames with a blowtorch (or under the grill/broiler). Each step is uncomplicated and you have these ready to enjoy in under an hour.
Biscuit layer
1. Preheat the oven and prepare the pan. Turn the oven on to 180°C (350°F) and line a 23cm (9-inch) square baking pan with parchment paper. (Image 1)
TIP: Leave an overhang around all sides (this will make it easier for you to remove the brownies once cooled)
2. Crush the biscuits and mix with butter. Add biscuits (or graham crackers) to a large sandwich bag a crush with a rolling pin until they are in crumbs. (Image 2)
Pour the biscuit crumbs into a bowl and mix in the sugar and butter until it resembles wet sand. (Image 3)
3. Pour into pan and compact. Pour the biscuit crumbs (or buttery graham cracker crumbs) into the prepared pan and pack them down firmly until in an even layer. (Image 4)
Bake for 10 minutes and then put to one side whilst you make the brownie layer.
TIP: I use a ⅓ measuring cup to do this. The base and sides are flat allowing me to get a super even base layer.)
Chocolate Brownies
1. Melt the chocolate and butter. I use a bain-marie to melt these two ingredients. Simply glaze a heatproof bowl over a saucepan of simmering water (make sure the bottom doesn’t touch though. (Image 5). Stir continuously until the chocolate has fully melted. (Image 6)
TIP: You can use the microwave for this step if you’d prefer. Heat the butter and chocolate in 20-second increments in the microwave, stirring in between each burst. Continue until all the chocolate and butter has melted.
2. Whisk the eggs and sugar. In a bowl, whisk the eggs, sugar and vanilla extract together until it's visibly paler and thicker. I use a handheld electric whisk but feel free to use a stand mixer or whisk by hand. (Image 7)
Add chocolate. Whilst still whisking, add in the melted chocolate and whisk until combined. (Image 8)
3. Sift in dry ingredients. Sift in the flour, cocoa powder, baking powder and salt (Image 9) and fold through. Don’t over mix otherwise you might deflate the eggs.
4. Pour into the pan and bake. Pour batter onto the top of the biscuit base and smooth out with an offset spatular. (Image 10)
Bake for 20-25 minutes until the sides are set but the centre has a slight jiggle.
Marshmallow layer
1. Add marshmallow fluff. Spoon the marshmallow fluff don't the brownie top and evenly distribute. Swirl with the back of a spoon. (Image 11 - 13). An option is to refrigerate the brownie for an hour to set the marshmallow fluff. (Note: I did not do this for my images as I wanted the oozing nature of the marshmallow fluff).
2. Torch the marshmallow. Using a kitchen blow torch, scorch the marshmallow fluff until the desired colour is achieved. (Image 14) (This bit is personal, some like it lightly coloured, like me, whilst others like a charred marshmallow. You do you!). If you don't have a blow torch, Heat under the grill (broiler). Place the pan under the grill and watch the marshmallow fluff slowly brown on top. Keep an eagle eye on it as it will turn burnt very quickly. Now they are ready to serve!!
TIP: To get those super clean, neat slices. Run a sharp knife under hot water, dry it and rub with vegetable oil before slicing. Wash under hot water, dray and rub the blade with oil after each slice.
Variations / Substitutions
Three components in this recipe. I get that it can feel like a recipe is getting a little complicated with three components. So I'm going to share with you two shortcuts that if you are time-poor, you can use!!
The Biscuit Base: If you want to really simplify the process of making these, then don't worry about making the biscuit base. Simply lay the graham crackers on the base of the prepared pan and pour the brownie mix directly onto the crackers and bake as per the recipe.
The Brownie Layer: Box Mix. Yep, I said. Go the box mix. I'd rather you enjoy this recipe using a shortcut than not trying this recipe out at all. Use your favourite box mix but I ask one thing, check out my Caramel Brownie ice cream where I have a couple of juicy, easy tips to make your boxed mix brownies heaps better.
The Marshmallow Layer: If marshmallow fluff is hard to come by where you are, then you can layer the brownie with mini marshmallows and toast them under the grill (broiler). I tested this, as you can see in the image below, but I found that when the marshmallows cooled, they went quite rubbery in texture. That was my personal experience, and I have read other blogs that successfully use mini marshmallows. But going off my experience I wasn't a fan of that text and so recommend marshmallow fluff instead.
Pro tips
TIP 1: Leave an overhang around all sides of your baking pan. The brownies can be removed from the baking pan seamlessly and easily.
TIP 2: Compact biscuit base. Make sure the biscuit base has been pressed down really well to encakier doesn't crumble apart once baked.
TIP 3: Heat the chocolate in the microwave for speed. Want to melt the chocolate and butter in the microwave instead? No problem, cube and chop ingredients until small and then microwave in 20-second increments until fully melted.
TIP 4: Use a hot knife to get clean cuts. Wait for the brownies to cool and then refrigerate for at least one hour before cutting. Then heat the blade of a sharp knife under hot water, wipe dry and slice. Heat and dry before every cut.
Frequently asked questions
Marshmallow Fluff, Creme or Spread is an American confectionary spread that's very similar to the taste of marshmallows but a different consistency. It's very light, airy, fluffy and sweet. it can be used to fill cases, top puddings or toast, as you would d normal marshmallows.
Furthermore, it comes in a jar. Not widely available in the UK, like it is in America, the larger supermarkets are starting to stock it in the condiments aisle. I bought mine in my Sainsbury's supermarket.
You'll know that they are done when they are set around the edges of the pan but have a slight jiggle in the centre. Remember, the brownies continue to cook internally when you pull them from the oven and place the pan on the wire rack. If you overbake the brownies you'll end up with a cakier inside as opposed to a fudgy inside.
Technically yes. Saying that though. the volume of ingredients will be a little too much for an 8x8inch baking pan in my opinion. If you decide to use all the ingredients in the smaller pan, then you'll have to adjust the brownie cooking time and it will be thicker.
Absolutely! Over in the UK, graham crackers aren't available, so we substitute them for digestive biscuits. If you have access to graham crackers, then definitely use them if you would prefer.
How to store and freeze
To store: Store your fudgy S'mores Brownies in an airtight container at room temperature for up to four days.
To freeze: The brownies can be frozen. I recommend freezing them in an airtight container, prior to covering them in fluff. Thaw overnight in the fridge and then layer the marshmallow fluff over the top.
Equipment you’ll need
- Medium bowl x2: A couple of medium size bowls to whisk eggs and sugar and to melt butter and chocolate in.
- Handheld Electric Whisk: To whip up the eggs and sugar until light and fluffy. Whisk by hand or with an electric stand mixer as an alternative.
- 23x23cm (9x9-inch) square baking pan: The perfect size pan for nine huge brownies or 16 squares.
More Decadent Chocolate recipes
If you tried this Fudgy S'mores Brownie Recipe or any other recipe on my website, please let me know how you go in the comments below. I love hearing from you. Also, please leave a star rating whilst you're there!
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This post was originally published in November 2019 but has been updated with new photos and new content. It also has a revised recipe utilising storebought marshmallow fluff as opposed to homemade marshmallow fluff as previously specified. This was to simplify the recipe and make it more approachable.
Fudgy S’mores Brownie Recipe
Ingredients
Biscuit base
- 210 g digestive biscuits (graham crackers), 16 biscuits
- 30 g granulated sugar
- 115 g unsalted butter, melted
Brownies layer
- 230 g unsalted butter
- 200 g dark chocolate 70% , chopped
- 200 g caster sugar
- 3 large eggs
- 1 tsp vanilla extract
- 125 g plain flour (all-purpose)
- 45 g cocoa powder
- ½ tsp salt
Marshmallow layer
- 210 g marshmallow fluff, 1 jar
Instructions
Biscuit base
- Pre-heat the oven and prepare the pan. Grease and line with parchment paper, the base and sides of a 23cm (9-inch) square baking pan. TIP. leave a paper overhang to make it easier to lift the S'mores Brownies out of the pan once baked.
- Crush the biscuits and mix with butter. Add the biscuits to a sandwich bag and seal closed. Crush the biscuits in the bag with a rolling pin until they are fine bread crumbs consistency. Pour the biscuit crumbs into a medium bowl and add the sugar and melted butter and mix until the crumbs start to clump and resemble wet sand. Alternatively, add the biscuits to the bowl of a food processor, pulse until in bread crumb consistency, then add sugar and melted butter and pulse until combined.
- Pour into pan and compact. Pour crumb mixture into the prepared baking pan and press down firmly until the base is level, smooth and compact. Bake for ten minutes and set aside on a wire rack until ready to use.
Brownies Layer
- Melt the chocolate and butter. Using a bain-marie (Bowl sat snuggly over a saucepan of boiling water. Note: don’t let the water touch the bottom of the bowl). Place the butter, chopped chocolate into the bowl and stir until melted and combined together.
- Whisk the eggs and sugar. In a medium bowl, with an electric beater or stand mixer, beat on medium speed, the eggs, sugar and vanilla extract until pale and fluffy. Pour in melted chocolate to eggs. Add the melted chocolate mixture and beat until combined.Sift in dry ingredients. Sift into the bowl the flour, cocoa powder and salt and fold until a few streaks of flour remain.
- Pour into the baking pan and bake. Pour the batter on top of the biscuit base and smooth it evenly with an offset spatular. Place in the oven and bake for 20-25 minutes. The edges should be firm, but the centre should have a slight jiggle when shaken gently. Remove from the oven, place the tray on a wire rack, and leave to cool completely. Use the parchment paper to lift the brownie out of the tin onto a cutting board.
Marshmallow layer
- Add the marshmallow fluff. Spoon the marshmallow fluff directly onto the brownies and evenly coat the top. Swirl with the back of a spoon. An option is to refrigerate the brownies to allow the marshmallow fluff to set before cutting. Torch the marshmallow. Using a blowtorch, torch the top of the meringue until browned. Or place under a grill (broiler) for a few minutes to toast the marshmallow fluff.Serve. Slice with a sharp knife and serve immediately.
All recipes are developed and tested in Metric grams. I strongly recommend that you bake using digital scales for a more accurate result. I have provided a conversion to US customary in the recipe but please note that I haven’t tested using this method.
Mary
Hi there! I happened to see a post for Smores bars in a book. I wanted to try a more simpler version. While searching I came across your website and found your recipe that is easy to work with. I have a query. In the brownie process, do you let the melted chocolate to cool completely before adding it to the whipped eggs?
Emma
Hi Riya, Thanks so much for finding the steps uncomplicated. If you break them down into the three component of biscuit base, brownie and marshmallow fluff- its really quite simple. In response to your question- no need to cool the chocolate down. You’ll be beating the melted chocolate instantly into the whipped eggs and this will bring down the temperature of the chocolate straight away.
Thanks Riya,
Emma
Sana
This looks so yumm. I would add a littles less fluff. I want to store the leftover fluff. Can you suggest how to do it and how long will it last please ? Thanks
Emma
Hi Sana, Thanks, it is a mighty decadent but delicious dessert. I haven’t stored the fluff before so I can’t recommend if it would hold up - I’m inclined to think that it won’t last being stored. I would suggest scaling down the fluff component instead. xx
Hannah Webb
Hey, I’m hoping to make these over the weekend. Please can I ask the best way to slice with the marshmallow Topping? Looking to have very clean slices! Thank you!
Emma
Hi Hannah- I recommend heating your knife blade under hot water wiping it dry, rubbing with oil then slicing through the marshmallow. Wipe the blade clean, heat again and re-oil as needed. It takes time but you will get photo worthy slices!
Theresa Alvarado
What is a substitute for castor sugar. I have never heard of it or seen it in a store.
Emma
Hi Theresa, You can use normal granulated sugar. We find caster sugar here in the UK and the grains of sugar are just finer than granulated sugar. x
Lauren Mer
How long will these last stored at room temperature
Thank you
Lauren
Emma
Hi Lauren- they’ll keep in an airtight container for up to 4 days 🙂
Lauren
I have made and they are AMAZING but the fluff has disintegrated and gone liquid like in places what have I done wrong?! Thanks
Emma
Hi Lauren, Hmmm there’s something not quite right with the meringue (which marshmallow fluff basically is). I am guessing that the meringue didn’t dry out whilst baking sufficiently. Therefor there was still too much moisture which when removed from the oven, seeped out. All ovens run differently so in your oven the bake time might need to be extended. Hope this helps xx
Michelle Sheyman
These look delicious. I plan on makign them tomorrow. Would this recipe work for a 12 pan cupcake pan instead of a 9inch square pan?
Emma
Hi Michelle- can't wait for you to try these s'mores brownies. And sure- just distribute the base and the brownie filling evenly between the 12 holes. I don't know the cooking time for the brownies though - it will be reduced that's for sure. Let me know how you go. Emma