This Mississippi Mud Cake includes a homemade chocolate cake with melted marshmallows and warm chocolate frosting poured on top. Trust me, it's as delicious as it sounds!

When I think of a chocolate lover's dream, this is the cake that comes to mind! It's called a “Mississippi Mud” cake because of the layers of soft marshmallow and chocolate that make up the topping and frosting. It's one of the easiest cakes to make, baked in a simple 9×13” pan.
I adapted the recipe from my favorite Hershey's Perfectly Chocolate Cake recipe but instead of buttermilk I used milk and sour cream for an extra moist and tender cake. The warm chocolate frosting is the same recipe I use for this popular Texas Sheet Cake. It's SO GOOD!
How to Make Mississippi Mud Cake:
- Combine dry ingredients: flour, sugars, cocoa powder, baking powder, baking soda and salt.
- Add wet ingredients: Add oil, eggs, vanilla, milk and sour cream and mix until combined. Reduce speed and carefully pour in the boiling water. Beat on high speed for 1 minute to add air to the batter.
- Bake: Pour batter into greased 9×13” pan and bake for 28-33 minutes.
- Add marshmallows. Remove cake from oven and sprinkle marshmallows all over the top of the hot cake, completely covering it. Return to oven for 2-3 minutes until marshmallows are puffed up. Cool cake before frosting.
- Make the Frosting: Melt butter in a small saucepan over medium-high heat. Add milk and cocoa powder and whisk well. Cook for about 2-3 more minutes, stirring constantly. Remove from heat and stir in vanilla and powdered sugar. Use an electric mixer to make the frosting smooth.
- Drizzle frosting over cake.

Make Ahead and Freezing Instructions:
The cake can be made 1-2 days in advance, stored covered at room temperature or in the refrigerator. The baked and frosted cake can be frozen for up to 3 months.

More Chocolate Cakes to love:
- The BEST Texas Sheet Cake
- Chocolate Cake with Chocolate Mousse Filling
- German Chocolate Cake
- Chocolate Mug Cake
- Dark Chocolate Cake
- Chocolate Raspberry Cake
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Recipe

Mississippi Mud Cake
Ingredients
- 2 cups all-purpose flour
- 1 ½ cups granulated sugar
- 1/2 cup light brown sugar , packed
- 3/4 cup unsweetened cocoa powder
- 2 teaspoons baking powder
- 1 ½ teaspoons baking soda
- 3/4 teaspoon salt
- 3/4 cup oil , canola or vegetable
- 2 eggs
- 1 teaspoon vanilla extract
- 6 Tablespoons milk
- 1/3 cup sour cream
- 1 cup boiling water
For topping:
- 10.5 ounce package mini marshmallows
- 1/2 cup butter (1 stick)
- 6 Tablespoons milk
- 3 heaping Tablespoons unsweetened cocoa powder
- 1 teaspoon vanilla extract
- 3 cups powdered sugar
Instructions
- Preheat oven to 350 degrees F. Lightly grease a 9×13” baking pan.
- In a large mixing bowl combine the flour, sugars, cocoa powder, baking powder, baking soda and salt.
- Add oil, eggs, vanilla, milk and sour cream and mix until combined. Reduce speed and carefully pour in the boiling water. Beat on high speed for 1 minute to add air to the batter.
- Pour batter into prepared pan. Bake for 38-45 minutes, or until a toothpick inserted in the center comes out clean.
- Remove cake from oven and sprinkle marshmallows all over the top of the hot cake, completely covering it.
- Return to oven (at 350 degrees F) for 3-5 minutes or until the marshmallows are just slightly puffed and melted.
- Allow cake to cool completely before drizzling frosting on top.
For the frosting:
- Melt butter in a small saucepan over medium-high heat.
- Add milk and cocoa powder and whisk well. Cook for about 2-3 more minutes, stirring constantly.
- Remove from heat and stir in vanilla and powdered sugar. Use an electric mixer to make the frosting smooth.
- Drizzle warm frosting immediately over cake. Refrigerate cake for about 30 minutes or until frosting has set. Store at room temperature.
- Next time try Mississippi Mud Brownies!
Notes
Nutrition
Have you tried this recipe?!
RATE and COMMENT below! I would love to hear your experience.x
I originally shared this post September 2015. Updated February 2021.
This post contains affiliate links.
My frosting was really runny compared to the one in the video
It should be slightly runny as you pour it over the cake and then it hardens as it cools.
This cake is reminding me of my childhood from Mississippi.
Love your recipes!!!
Thank you so much!
I had never heard of this 🙁 I have seen other versions since & yours looks the best. I’m so going to make it for a potluck this wknd. Could the cake be made a day ahead of time & then go from there the next day?
Also does it matter what kind of cocoa powder you use? I’m thinking for one it needs to be sweetened vs unsweetened. Never baked with it before.
I use unsweetened for both 🙂
Yum! I’d love to hear how you like it! Yes, you could make the cake in advance. Bake it, let it cool completely, then cover it well at room temp.
Love your recipes and thank you so much.
Maria
My husband was just telling me how much he loves this cake–and I have never even tried it myself. Time to make!
Thanks Kristen! Hope you enjoy it 🙂
Oatmeal cake is so yummy. And I like to think that it is a little healthier too. I will have to change things up and give your recipe a try. It looks amazing.
Hi Lauren. Great Recipe. We posted this on “Rad Cake Network” Facebook page. ❤️
I just made this for my husband’s birthday, and it was AMAZING! Thank you so much for sharing it!
Thanks for sharing Amanda! I’m glad it made a great birthday cake!!
The pictures are mouthwatering!
Thanks for sharing 🙂
i love choclate cakes, thank you very much for the inspiration