This classic Mississippi Mud Cake delivers pure chocolate bliss with every heavenly bite. A favorite Southern dessert that perfectly balances rich, moist chocolate cake with gooey marshmallows and a decadent chocolate frosting. Ready in just an hour, this crowd-pleasing treat packs 633 calories of pure indulgence. Whether you’re planning a family gathering or simply treating yourself, this foolproof recipe creates an irresistible cake that’ll have everyone begging for seconds.

Main Ingredients

Flour & Sugars: 2 cups all-purpose flour, 1½ cups granulated sugar, ½ cup packed light brown sugar for perfect sweetness balance
Cocoa Mix: ¾ cup unsweetened cocoa powder for rich chocolate flavor
Leavening Agents: 2 tsp baking powder, 1½ tsp baking soda, ¾ tsp salt for ideal rise
Wet Ingredients: ¾ cup oil, 2 eggs, 1 tsp vanilla, 6 tbsp milk, ⅓ cup sour cream for moisture
Special Addition: 1 cup boiling water to enhance chocolate flavor

Topping Ingredients

Marshmallow Layer: 10.5 oz mini marshmallows for gooey goodness
Frosting Base: ½ cup butter, 6 tbsp milk, 3 tbsp cocoa powder
Finishing Touch: 1 tsp vanilla, 3 cups powdered sugar for smooth texture

Baking Instructions

Preparation: Heat oven to 350°F and grease a 9×13″ pan
Mix Dry Elements: Combine flour, sugars, cocoa, leavening agents in a bowl
Wet Addition: Mix in oil, eggs, vanilla, milk, sour cream until smooth
Water Integration: Carefully add boiling water, beat for 1 minute
Initial Bake: Pour into pan, bake 28-33 minutes until done
Marshmallow Magic: Top hot cake with marshmallows, return for 2-3 minutes

Frosting Steps

Butter Base: Melt butter over medium-high heat
Chocolate Mix: Add milk and cocoa, whisk 2-3 minutes
Final Touch: Add vanilla and sugar, blend until smooth
Assembly: Drizzle warm frosting, chill 30 minutes until set

Cooking Techniques

This cake uses a neat trick to make it super moist – adding boiling water at the end! When you mix in that hot water, don’t worry if the batter seems thin. That’s exactly what we want! The secret to getting those marshmallows just right is timing. You want them slightly puffy and melty, but not completely melted down. Keep an eye on them during those final 2-3 minutes in the oven – they should look like little clouds on top of your cake.

Variations

Love nuts? Add 1 cup of chopped pecans or walnuts to the frosting for extra crunch. For an extra chocolatey version, swap regular cocoa powder with dark cocoa powder. If you’re out of sour cream, plain Greek yogurt works great too! Want to make it even more fun? Try using colored marshmallows for birthday parties or holidays.

Storage Tips

Your Mississippi Mud Cake will stay fresh at room temperature for up to 4 days when stored in an airtight container. The marshmallow layer might get a bit sticky – that’s totally normal! If you need to stack pieces in a container, place wax paper between layers to prevent sticking. While you can refrigerate this cake, it tastes best when served at room temperature, so let it sit out for about 30 minutes before eating if it’s been chilled.

Serving Suggestions

This rich cake is amazing on its own, but try warming each slice for 10-15 seconds in the microwave – it makes the marshmallows all gooey again! Add a scoop of vanilla ice cream on the side for an extra special treat. For a pretty presentation, dust the plate with a little cocoa powder before adding your slice. Coffee or cold milk make perfect drinks to serve alongside this decadent dessert.