S’mores Graham Cracker Marshmallow Dump Cake

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This S’mores Graham Cracker Marshmallow Dump Cake hits all the nostalgia buttons.

It reminds me of campfires, sticky fingers, and late-night marshmallow roasts as a kid.

The marshmallows get all gooey, the chocolate melts into pockets of heaven, and the graham crackers give that perfect crunch.

It’s one of those desserts that’s stupid easy to make but somehow looks and tastes like you spent all day on it.

I bring it to pretty much every casual get together or holiday party, and people always ask for the recipe.

Ingredients

1 box chocolate cake mix (15.25 oz)
1 1/2 cups graham cracker crumbs (about 10–12 full sheets, crushed)
2 cups mini marshmallows
1 cup chocolate chips
1/2 cup unsalted butter, melted
1/2 cup heavy cream
1/2 cup sweetened condensed milk
1/4 cup whole milk
1 tsp vanilla extract
1/4 cup granulated sugar
1/2 tsp ground cinnamon, optional if I’m feeling cozy
1/4 cup extra mini marshmallows for the top
2 tbsp crushed graham crackers for garnish

Why I Love These Ingredients

The chocolate cake mix gives it that rich, chocolatey base, graham cracker crumbs add crunch and sweetness, and marshmallows…well, they melt into all sorts of gooey goodness. The chocolate chips? Melted pockets of happiness in every bite.

Butter keeps it moist, cream makes it luxuriously gooey, and sweetened condensed milk adds that sticky, fudgy vibe.

Cinnamon is optional but gives it a warm, cozy note that makes it feel like a hug in dessert form. Extra marshmallows and crushed graham crackers on top?

Totally optional but totally worth it.

Making the Cake

First I preheat my oven to 350°F and grease a 9×13-inch baking dish. I like using butter but non-stick spray works too.

Next I crush the graham crackers. I usually toss them in a zip-top bag and roll over them with a pin until I have 1 1/2 cups. Food processor works if I’m lazy, but rolling by hand is oddly satisfying.

Then I whisk together the melted butter, heavy cream, sweetened condensed milk, whole milk, and vanilla extract until smooth.

After that, I stir in the sugar and cinnamon if I’m using it.

Now the fun part, I layer the cake. I spread the graham cracker crumbs over the bottom of the pan, then sprinkle the mini marshmallows and chocolate chips over that.

It’s already starting to look like s’mores heaven. I pour the dry cake mix evenly on top,

and here’s the magic of a dump cake I don’t touch it with a spoon.

The wet mixture goes right over the top and soaks in as it bakes.

I like to sprinkle extra mini marshmallows on top so they get all melty and golden. Then it goes in the oven for about 35–40 minutes.

I keep an eye on it because I love when the top is slightly crispy but the inside is gooey.

Once it’s out, I sprinkle crushed graham crackers over it for extra crunch.

Serving

I love scooping it into bowls while it’s still warm and topping it with vanilla ice cream or whipped cream.

Sometimes I drizzle chocolate syrup on top too, just because. It’s perfect with hot cocoa or coffee for a cozy vibe.

For parties, I cut it into squares and serve it on a platter with extra marshmallows and chocolate for a fun, campfire feel.

Leftovers

If there are any, I keep them in an airtight container in the fridge for up to 5 days.

To reheat, I zap a portion in the microwave for 15–20 seconds or warm it in the oven at 300°F for 10 minutes.

The marshmallows stay melty, and the chocolate is still all soft and gooey.

My Tips

I pulse the graham crackers in a food processor if I want them fine or crush by hand for a rustic look. I try to spread the marshmallows evenly so every bite has goo.

Chocolate chips can be milk or dark depending on how rich I’m feeling.

If the marshmallows start browning too fast, I cover the pan with foil for the last 10 minutes.

I also make sure the cake mix is spread evenly so there aren’t clumps, that way every bite is perfect.