These indulgent Mississippi Mud Brownies deliver pure chocolate bliss in every fudgy bite. The perfect balance of rich cocoa and sweet marshmallow creates an irresistible Southern classic that’s ready in just 45 minutes.
With a prep time of only 20 minutes, you’ll have warm, gooey brownies that bring comfort and joy to any gathering. Whether it’s a family dessert or potluck favorite, these decadent treats never fail to make chocolate lovers smile.
Ingredients
For the Brownies:
- Cocoa Powder: 1/3 cup unsweetened, creates rich chocolate base
- Fats: 1/2 cup oil + 1/2 cup softened butter for perfect texture
- Sugar: 2 cups granulated for ideal sweetness
- Eggs: 4 large, provides structure and richness
- Vanilla Extract: 2 teaspoons for depth of flavor
- Flour: 1 1/2 cups all-purpose, the foundation
- Salt: 1 teaspoon to enhance flavors
- Mini Marshmallows: 3 cups for that classic topping
For the Frosting:
- Butter: 1/2 cup melted, creates smooth base
- Cocoa Powder: 1/3 cup unsweetened for chocolate richness
- Evaporated Milk: 1/3 cup for creamy texture
- Vanilla Extract: 1 teaspoon for flavor boost
- Powdered Sugar: 3-3 1/2 cups for desired consistency
Instructions
- Preparation: Heat oven to 350°F and grease a 9×13″ pan
- Base Mix: Blend oil with cocoa powder until smooth
- Wet Ingredients: Mix in softened butter, sugar, eggs (one at a time), and vanilla
- Dry Addition: Fold in flour and salt until just combined
- First Bake: Pour into pan and bake 25-30 minutes until toothpick comes clean
- Marshmallow Layer: Top with marshmallows and return to oven 2-3 minutes until puffy
- Cooling Phase: Let brownies cool completely before frosting
- Frosting Creation: Beat melted butter, cocoa, milk, vanilla, and powdered sugar until smooth
- Final Touch: Spread frosting over cooled brownies and cut into squares
Baking Tips
Want super fudgy brownies? Keep a close eye on the baking time – when your toothpick comes out with just a few moist crumbs, they’re perfect! The marshmallow layer needs just 2-3 minutes to puff up nicely.
If you see them getting too brown, pop them out right away. Your brownies will continue cooking slightly as they cool in the pan.
Storage Tips
These beautiful brownies stay fresh for up to 5 days when stored in an airtight container at room temperature. The marshmallow layer makes them a bit tricky to stack, so try placing wax paper between layers.
Want to make them last longer? You can freeze them for up to 3 months! Just wrap them individually in plastic wrap and pop them in a freezer bag.
Serving Suggestions
Take these brownies from amazing to absolutely incredible! Warm them up for 10-15 seconds in the microwave – the marshmallows get all gooey and the frosting softens just right.
Add a scoop of vanilla ice cream while they’re still warm for the ultimate dessert. For fancy parties, cut them into tiny squares and pop them on a pretty platter with a light dusting of cocoa powder.
Helpful Substitutions
Out of evaporated milk? Regular milk works fine in the frosting – just use a bit less since it’s thinner. If you don’t have mini marshmallows, cut regular ones in half.
For a dairy-free version, swap the butter for dairy-free margarine and use almond milk in the frosting. The brownies might be a tiny bit less rich, but they’ll still taste amazing!
Mississippi Mud Brownies
Equipment
- 9×13 inch baking pan
- Electric mixer
- Mixing bowls
Ingredients
For the Brownies
- 1/3 cup unsweetened cocoa powder
- 1/2 cup oil vegetable or canola oil
- 1/2 cup butter softened
- 2 cups granulated sugar
- 4 large eggs
- 2 teaspoons vanilla extract
- 1 1/2 cups all-purpose flour
- 1 teaspoon salt
- 3 cups mini marshmallows
For the Frosting
- 1/2 cup butter melted
- 1/3 cup unsweetened cocoa powder
- 1/3 cup evaporated milk
- 1 teaspoon vanilla extract
- 3-3 1/2 cups powdered sugar
Instructions
- Preheat oven to 350 degrees F. Grease a 9×13″ pan with non-stick cooking spray.
- In a large mixing bowl, pour oil over cocoa powder and mix.
- Add softened butter and mix until smooth. Add sugar and mix for 1 minute. Add eggs, one at a time, mixing after each addition. Add vanilla and mix.
- Add flour and salt and stir to combine.
- Pour batter into prepared pan. Bake for 25-30 minutes or until a toothpick inserted into the center comes out clean.
- Remove brownies from the oven and sprinkle the marshmallows evenly on top. Return to the oven for 2-3 minutes or until the marshmallows are puffed. Remove from oven and allow them to cool completely.
- Once brownies are cool, make the frosting. For the frosting: Add melted butter, cocoa powdered, evaporated milk, vanilla, and 2 cups of powdered sugar to a mixing bowl and beat with electric beaters until smooth.
- Add more powdered sugar, a cup at a time, mixing well, until you reach your desired frosting consistency. I usually use about 3 ¼ cups powdered sugar.
- Spread frosting over the cooled brownies and cut into squares. I’ve found a plastic knife works best to cut them, or if you make them 1 day in advance they are much easier to cut.
