This Mississippi Mud Cake is made with layers or rich chocolate cake, gooey marshmallows, and chocolate fudge frosting. This is the best recipe. Serve this cake at your next party and watch it disappear in minutes!
For the Cake
- 1 3/4 c all purpose flour
- 1 3/4 c granulated sugar
- 2 tsp baking soda
- 1 tsp baking powder
- 1 tsp salt
- 3/4 c unsweetened cocoa powder (a premium brand like Callebaut cocoa powder or Valrhona cocoa powder will take this cake to the next level!)
- 2 tsp espresso powder (optional, but recommended)
- 1/2 c vegetable oil or canola oil
- 2 eggs (lightly beaten, room temp)
- 2 tsp vanilla extract
- 1/2 c sour cream (at room temp)
- 1/2 c water + 1 c water (measure out and set the 1 c aside)
- 1 (10oz or 283g) bag of mini marshmallows (for after the cake is baked)
For the Frosting
- 1 c dark chocolate chips or chopped chocolate
- 8 Tbsp unsalted butter (cut into cubes)
- 3 c powdered sugar
- 1 tsp vanilla extract
- 6 Tbsp hot water
To Make the cake
- Preheat oven to 350°F. Grease a 9x13 size pan with shortening or cooking spray and set aside.
- In a large mixing bowl, whisk together the flour, cocoa powder, sugar, baking soda, baking powder, salt, and espresso (if using) powder. Set aside.
- In a separate large bowl, add oil, eggs and vanilla until combined on medium-high speed using a stand mixer fitted with a paddle attachment or electric hand mixer. Add the sour cream and 1/2 c of water. Mix again until combined.
- Add the wet ingredients into the dry ingredients and mix until they've just begun to combine.
- Using the stove or microwave, heat up the remaining cup of water until boiling.
- Then, add about 1/4 of the hot water and mix. Stop to scrape the sides and bottom of the bowl well.
- Stop mixing and add more of the hot water (about half of the remainder). Mix again, and scrape the bowl down.
- Add the remainder of the water and repeat the mixing process until batter is completely combined. It will be very thin.
- Pour batter into prepared pan.
- Bake for 40-45 minutes, or until the center of the cake comes out clean when a toothpick is inserted. Baking times vary, so keep an eye on the cake at the 40 minute mark.
- Remove cake from the oven and turn the oven off.
- Add all of the mini marshmallows to the top of the hot cake in one even layer, completely covering the top. Place back into the oven for 2-3 minutes until marshmallows have puffed. They should not be completely melted marshmallows.
- Allow cake to cool completely.
To Make the Frosting
- Prepare the frosting by placing the chocolate chips or chopped chocolate and butter in a microwavable bowl. Microwave on high in 15 second intervals, stirring in between, until the chocolate and butter has melted.
- Add the powdered sugar and vanilla and mix. The mixture will be very thick at this point.
- Add the hot water to the bowl and mix frosting smooth. If you see any separation of butter, continue to mix until it's combined. Sometimes pulling out the hand mixer helps here!
- Pour the warm chocolate frosting over the cooled cake.
- Allow icing to set for 30 minutes or refrigerate cake. Note, the frosting will firm up when the cake is chilled so if you want the icing to still be soft, do not refrigerate.
Recipe by Owlbbaking.
- 1 cup of buttermilk can be substituted for the 1/2 cup of sour cream and 1/2 cup water. You may also substitute full fat Greek yogurt in place of the sour cream. I also like to mix the sour cream and 1/2 cup water in a small cup before adding it to the egg/oil mixture.
- Avoid pouring all of the hot boiling water in at once (I made this mistake in my video!). It's best to temper the water in slowly.
- For some crunch, feel free to add chopped pecans to the frosting!
Keywords: Mississippi Mud Cake, mud cake, chocolate cake, marshmallows, chocolate fudge frosting, cake with marshmallows, Mississippi mud cake recipe