Where are my S’mores fans at? I will be the first to admit that, honestly, actual S’mores are not really my thing. In fact, I will almost always pass on a regular ole’ S’more. I am just not a fan of marshmallows really. Especially raw, uncooked marshmallows. I think they are so gross. However, S’mores flavored desserts like this cake for example, have my heart. I am all about a S’mores style dessert as long as the marshmallow is not raw and the graham cracker portion is either in crust, cake or cake form, rather than just a plain old graham cracker. Heck, one of my favorite cookies of all time is a S’mores Cookie.

This S’mores Sheet Cake has one of my very favorite cake bases of all time, my graham cracker cake. It’s basically like eating a soft version of an actual graham cracker. It is insanely delicious. I have a Raspberry Cheesecake Sheet Cake recipe coming very soon that will also feature this same cake base. Anyway, back to the S’mores Cake. On top of the graham cracker cake is a toasted marshmallow frosting, featuring REAL toasted marshmallows, it’s then topped with a rich homemade chocolate ganache and then obviously topped with my famous “crack” aka graham crackers baked in butter and brown sugar. You can’t go wrong with this cake, it is a definite crowd pleaser!



Tips & Tricks
- I prefer to split this cake making process into 2 separate days so I don’t feel overwhelmed with the process. On day 1 I make the cake and the “crack”. I store the cake covered on the countertop and put the “crack” in a Ziploc bag until the next day. On day 2 I make the frosting and the ganache and assemble the cake. This isn’t necessary but if you are wanting to split it up, it can be done!
- It is extremely important that you don’t walk away from the oven while your “crack” is broiling that last minute. You may not even need the full minute so watch it very closely. You want to remove it just when its a dark golden brown but not burnt!
- I prefer to eat this cake cold! Store it in the fridge for a few hours before eating. But make sure to try it at room temperature too, because it’s also delicious. Just my personal preference!


S’mores Sheet Cake
- Prep Time: 90 minutes
- Cook Time: 35 minutes
- Total Time: 2-2 1/2 hours
- Yield: 24 1x
Description
Homemade graham cracker cake base frosted with toasted marshmallow frosting made from actual roasted marshmallows and then topped with chocolate ganache and an addicting graham cracker “crack”.
Ingredients
For the cake:
- 1 1/2 cups all purpose flour
- 1 1/2 cups graham cracker crumbs
- 1 1/2 tsp baking powder
- 3/4 tsp baking soda
- 3/4 tsp salt
- 3/4 cup sour cream (room temp)
- 1 tbsp vanilla extract
- 3 tbsp vegetable oil
- 2 1/4 sticks salted butter (softened)
- 3/4 cup sugar
- 3/4 cup brown sugar
- 4 eggs (room temp)
- 3/4 cup buttermilk (room temp)
For the frosting:
- 24 large marshmallows
- 1 1/2 cups powdered sugar
- 3 sticks salted butter (softened)
- 1 tsp vanilla extract
- 1 1/2 jars marshmallow cream (roughly 10–11 oz)
For the ganache:
- 2 cups semi sweet chocolate chips
- 1 cup heavy whipping cream
For the “crack”:
- 24 graham cracker sheets
- 3 sticks salted butter, melted
- 2/3 cup brown sugar + 1/2 cup reserved
- 1/4 tsp salt
Instructions
For the “crack”:
- Preheat your oven to 400 degrees.
- Break up your graham crackers into roughly quarter sized pieces.
- In a medium sized bowl mix together broken up graham crackers, melted butter, 2/3 cup brown sugar and salt. Stir to combine.
- Line a half sheet pan with tinfoil and spray with cooking spray.
- Evenly spread out the graham cracker mixture onto the pan. Sprinkle evenly with remaining 1/2 cup brown sugar.
- Bake for 10 minutes.
- At the 10 minute mark, turn your oven to broil and let the mixture get a toasty brown color. Don’t walk away from the oven at this point or look away from your mixture while it is in the oven. It’ll burn in the matter of seconds so keep a close eye on it. It should only take like 60 seconds are so!
- Remove from the oven and let cool completely.
- Once cool, break mixture into small chunks and set aside while you make the cake.
For the cake:
- Preheat your oven to 350 degrees.
- In a stand mixer or with a hand mixer, cream together butter and sugars for 4 minutes until smooth.
- Add eggs one at time, scraping down the sides and bottom of the bowl after each addition.
- Mix for 2 minutes once all the eggs are added.
- Add vanilla, sour cream and oil and mix for an additional 2 minutes.
- In a separate medium sized bowl whisk together all dry ingredients.
- Alternating between the dry mixture and the buttermilk add them to the butter mixture, always starting and ending with the dry mixture. Mix until no flour streaks remain. Make sure and scrape down the sides and bottom of the bowl.
- Spray a half sheet pan liberally with cooking spray and pour cake batter evenly into the pan.
- Bake for 18-22 minutes or until a toothpick entered in the center comes out with a few moist crumbs on it.
- Set aside to cool while you make the frosting.
For the frosting:
- Turn your oven to broil and line a half sheet pan with parchment paper.
- Spread marshmallows evenly onto the sheet pan and add them to the hot oven. Do not walk away! Watch the marshmallows and roast them until they turn a nice dark golden brown on top. Remove the pan, flip the marshmallows over with tongs and repeat the roasting process. They should be nice and toasted on both sides.
- Set aside to cool slightly while you prepare the rest of the frosting.
- In a stand mixer or with a hand mixer, mix together butter and powdered sugar until smooth. Add vanilla and marshmallow cream and mix on medium high until light and fluffy, about 2 minutes.
- With your mixer on medium speed, slowly add your slightly cooled toasted marshmallows to the mixture a few at a time.
- Once they are all added beat the frosting on high speed for 2 minutes until everything is homogeneous.
For the ganache:
- In a microwave safe dish, heat cream for 60-90 seconds in the microwave.
- Pour hot cream over the chocolate chips and let them sit for 5 minutes.
- After 5 minutes stir together the cream and chocolate until completely smooth. (You may have to heat the mixture for an additional 30 seconds or so to get everything completely melted).
Assembly:
- Frost the cooled cake with the toasted marshmallow frosting.
- Evenly spread the chocolate ganache over top of the marshmallow frosting.
- Sprinkle the “crack” evenly over top of the ganache.
- Serve immediately, or store in the refrigerator for 2 hours for a more “set” cake.
- Store any leftovers in the fridge for up to 5 days.
- Category: Dessert
Keywords: S’mores, Marshmallow, Sheetcake, Cake, Dessert
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