I’ve been wanting to make a s’mores cake FOREVER! I keep seeing them on Pinterest and some of my favorite blogs but I wasn’t sure how I’d go about it… A few weeks ago I made my pumpkin pie cake and had a surge of inspiration. The baked graham cracker crumble I made for that cake would be PERFECT for a s’mores cake! From there, I added chocolate buttercream, a graham cracker cake, and a gooey delicious marshmallow fluff (which I will definitely be making more of soon) and drizzled it with dark chocolate (which cools and solidifies for an extra crunch).
If you find cake decorating to be a bit intimidating then check out my How to Decorate a Cake post, it has lots of helpful tips and a full how to video.
about the Graham cracker crumble
I love the crunch from the Graham cracker crumble and the solidified chocolate in this cake, it contrasts well with the gooey marshmallow fluff! When you make the crumble make sure to press it into a nice compact layer but leave some bigger pieces for extra crunch. Bake until golden brown and make sure to rotate the baking sheet halfway through so you get a nice even brown. Add the crumble all over the cake and inside too. It’s so delicious and adds wonderful texture.
Toasting the marshmallow fluff is optional but so worth it! I have a little kitchen torch at the ready in my drawer and I can’t tell you how handy it’s been. As to can see, the marshmallowy fluff is REALLY gooey! Next time, I might try adding some more of the graham cracker crumble just underneath that top layer of toasted marshmallow to add some extra crunch.
How to Make S’more’s Cake
- Pipe a ring of chocolate buttercream onto the first layer
- Fill with marshmallow. I find piping is the easiest and least messy way.
- Sprinkle with the crumble.
- Add a drizzle of the melted chocolate, stack the next cake layer on and repeat steps 1-4 until you have all four layers.
- Cover the cake in buttercream.
- Smooth the side using a bench scraper and the top with an offset spatula. I recommend chilling the cake for a bit to make sure it’s nice and stable before proceeding.
- Add the graham cracker crumble to the base by pressing with your hand. You can dust away the excess afterward.
- Use a large star tip to pipe the marshmallow on top. I also swirled it a bit with a spatula but that’s totally optional.
- Use a torch to toast the marshmallow. This is best done just before serving so it’s nice and gooey!
pro tips for this recipe
- If you’re not using 6-inch pans, double the recipe for 8-inch pans or triple the recipe for 9-inch pans.
- If you don’t have access to Graham crackers you can substitute digestive biscuits for them.
- I recommend adding the graham cracker crumble in between each layer. It has so much crunch that I guarantee you’ll want more!
- You can substitute whole milk yogurt for the sour cream if desired, I do it all the time and can’t really tell the difference.
- To get FLAT layers that are moist inside and out try using cake strips! You can buy a set on the shop page or make your own from foil and paper towels at home. I made a whole blog post on it so check it out if you’re interested!
If you love this recipe try these out!
If you’ve tried this cake out then don’t forget to rate the recipe and let me know how you got on in the comments below, I love hearing from you!
S'mores Cake
Video
Ingredients
For the Cake
- 1 1/4 cup all purpose flour 150g
- 3/4 cup graham cracker crumbs 63g
- 1 tsp baking powder 4g
- 1/2 tsp salt
- 1/2 tsp baking soda 3g
- 1/2 tsp cinnamon 1g
- 1/4 tsp allspice 250mg
- 1 cup unsalted butter 230g, room temp
- 1/2 cup sugar 100g
- 1/2 cup light brown sugar 100g
- 3 large eggs
- 1 egg white
- 1/2 cup buttermilk 118mL
- 1/2 cup sour cream 115g
- 1 tbsp vanilla 15mL
For the crumble
- 4 graham crackers roughly crumbled
- 4 tbsp unsalted butter 42g, melted
- 1/2 tsp cinnamon 1g
- 1 pinch salt
- 1/4 tsp all spice 250mg
For the Buttercream
- 1 1/2 cups unsalted butter 340g, room temp
- 1 1/2 pounds powdered sugar 680g
- 1 tsp salt
- 1 cup dark or semisweet chocolate 175g, melted and cooled
For the Fluff
- 1 cup sugar 200g
- 1/2 cup light corn syrup 118mL
- 4 large egg whites room temp
- 1/4 tsp salt
For the Chocolate Drizzle
- 3/4 cup dark chocolate melted and cooled
Instructions
For the Cake
- Set oven to 350F. Butter and flour 3 6" cake pans (I recommend using cake stripes as well.
- Whisk all the dry ingredients together in a medium bowl. In a separate bowl, mix the buttermilk, vanilla and sour cream.
- Cream the butter in a stand mixer and add sugars. Mix until light and fluffy.
- Add the eggs and white in one at a time mixing until incorporated.
- Add the flour mixture and the buttermilk mixture in alternating batches. Starting and ending with the flour mixture. Mix until just combined, give the bowl a final scrape with a spatula to get any unmixed parts on the sides and bottom.
- Pour batter into your pans and bake for about 30 minutes or until a knife comes out clean from the center.
For the Buttercream
- Beat the butter until light and fluffy, add in confectioner's sugar in several batches and beat until incorporated. Drizzle in melted chocolate and mix until well combined. If buttercream is too thick at this point you can add some cream or milk, a tablespoon at a time until desired consistency is reached.
For the Fluff
- Add 2/3 cup sugar and corn syrup to a small sauce pot and heat on medium high. Track the temperature with a candy thermometer you will want to pour into the egg whites when it is 240F.
- In a stand mixer start beating the egg whites starting on low but gradually gradually increasing to medium-high speed. Add in 1/3 cup of sugar while the egg whites are stiffening. Once you are at the soft peak stage slowly drizzle in the 240F sugar syrup into the mixer.
- Allow the mixer to run for about 10 minutes to allow the fluff to cool.
- You can use immediately, if the fluff looses it's texture give it a good wisk or run the mixer for a few seconds to bring it back.
For the Crumble
- Mix the melted butter and graham cracker crumbs together well.
- Flatten out to about 1/4" onto a baking sheet lined with parchment paper.
- Bake for about 10 minutes at 350F or until you see a slight browning.
- Allow to cool and then crumble the mixture roughly allowing some larger pieces to remain.
Assembling
- Pipe a ring of the chocolate buttercream on each layer and fill with marshmallow fluff. Sprinkle with graham cracker crumble and drizzle with melted chocolate.
- Apply a thin crumb coat and allow to set in the refrigerator for about 20 minutes.
- Coat with chocolate buttercream, smooth edges with an offset spatula.
- press cracker crumbs onto the bottom third of the cake and then pipe the fluff onto the top.
- Flame the fluff with a torch and cake is ready to serve.
Notes
- If you’re not using 6-inch pans, double the recipe for 8-inch pans or triple the recipe for 9-inch pans.
- I recommend adding the graham cracker crumble in between each layer. It has so much crunch that I guarantee you'll want more!
- You can substitute whole milk yogurt for the sour cream if desired, I do it all the time and can’t really tell the difference.
- To get FLAT layers that are moist inside and out try using cake strips! You can buy a set online or make your own from foil and paper towels at home. I made a whole blog post on it so check it out if you’re interested!
- Torching the marshmallow on top is optional but so worth it!
Nutrition
In the midst of making this today. Mild panic when making the marshmallow fluff as I put the 1c of sugar and the corn syrup in a pan as specifies in the ingredient list. However, instrunctions mention just 2/3 c of sugar with no mention elsewhere of the remaining 1/3. I beat the egg whites on their own and added th syrup drizzle. So far, it seems to have worked out ok. I wonder if perhaps the mysterious 1/3 c should have been whisked in with the egg whites?
Hi, I have just tried making the buttercream. No matter how long i beat it, i still taste that little sand texture. Is that normal?
but the buttercream is super fluffy!
Hi Joyce! Did you use confectioners’ sugar for the buttercream? There shouldn’t be any sandy texture if so.
This cake looks great! How would you recommend adjusting time if using 8 inch pans?
I might add 10 minutes but I use cake strips, which affects the time a bit as well. Maybe just keep a hawk eye on that oven?
It was the most delish batter anyway! Thank you for sharing it. Yummo!
Hi! I loved your video so much that I HAD to try this cake. I noticed that there’s no levening agent & thought that maybe the sour cream & buttermilk might have some reaction? But my cake didn’t rise. Yours looks pretty fluffy! What’d I do wrong?
Hi June! Unfortunately my website was having some major glitches this morning and a couple lines of ingredients got deleted. So sorry about that, I’ve updated the recipe though. :/
This looks great! I’m going to make it this weekend. Would the batter be enough to use in two 8″ or 9″ pans? Or should I double it?
Thank you!
Hi Lisa,
It should be enough for two pans that size for sure. But you could always double it an make a tablet 3 or 4 layer cake 😀