Mississippi mud brownies feature a rich, chocolate walnut brownie base topped with a layer marshmallows and a chocolate fudge frosting.
Mississippi Mud
Mississippi mud desserts like these brownies come from the state of the Mississippi and became popular in the 1970’s. These chocolate desserts like cakes, pies and brownies were so-named since they resembled the muddy banks of the Mississippi River. The popularity of these desserts quickly spread across the country, including in many Midwestern states like my home state that borders the Mississippi River.
How to Make this Recipe
These Mississippi mud brownies feature a rich, chocolate walnut brownie base topped with a layer marshmallows and a chocolate fudge frosting. The frosting for these brownies is the same frosting that I use on these chocolate sour cream drops and is incredibly fudgy – be sure to read the tips below when making this frosting since it sets up fast. To achieve the rich, chocolate taste for the brownies, use a Dutch process cocoa. If you are not a fan of nuts, you can easily omit them in this recipe.
Ingredients for the Brownies
- Chopped walnuts
- Unsalted butter
- Cocoa powder, Dutch process preferred
- Granulated sugar
- Eggs
- Vanilla extract
- All-purpose flour
- Baking powder
- Salt
Spread chopped walnuts on an ungreased sheet pan and bake at 350°F degrees for 6-8 minutes. Cool and store if not using right away. Preheat oven to 350°F. Grease an 8”x8” baking dish. In medium-sized saucepan, melt butter with cocoa powder over medium heat. Once butter has melted, remove saucepan from heat and add sugar, eggs, vanilla, flour, baking powder and salt. Stir in toasted walnut; pour into greased baking dish. Bake 20-25 minutes or until brownies begin to pull away from sides of pan. Cool pan completely on wire rack before frosting.
Ingredients for the Frosting
- Granulated suar
- Cocoa powder, Dutch process preferred
- Light corn syrup (such as Karo)
- Heavy cream
- Salt
- Vanilla extract
- Powdered sugar
- Mini marshmallows
Combine all ingredients except for vanilla and powdered sugar in medium sized saucepan over medium heat. Bring to a full boil and cook 2 minutes, stirring occasionally. Remove from heat and stir in vanilla. Allow to cool to lukewarm, then add powdered sugar and whisk until smooth. Evenly spread marshmallows on top of cooled brownies; pour frosting evenly on top. Cut into squares.
Tips for Mississippi Mud Brownies
- The walnuts can be toasted in advance; toasted nuts will keep sealed in an airtight container for about two weeks
- You can use regular cocoa powder in this recipe instead of Dutch process; however, the chocolate flavor will not be as rich
- If frosting is too thick, thin it out with additional heavy cream
- Once the powdered sugar has been mixed into the frosting, spread the frosting quickly before it sets up
- Brownies will keep in an airtight container for up to 3 days
- Brownies will freeze well if in an airtight container for up to 4 weeks
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Mississippi Mud Brownies
Equipment
- mixing bowls of various sizes
- 8" x 8" square baking pan
- medium sized saucepan
Ingredients
For the brownies:
- 1/2 cup unsalted butter
- 1/3 cup cocoa powder, Dutch process preferred
- 1 cup granulated sugar
- 2 large eggs
- 1 teaspoon vanilla extract
- 1/2 cup all-purpose flour
- 1/4 teaspoon baking powder
- pinch of salt
- 1/4 cup toasted walnuts, chopped
For the frosting:
- 1/2 cup granulated sugar
- 2 tbsp cocoa powder
- 1 tbsp light corn syrup
- 1/4 cup heavy cream or half and half
- pinch of salt
- 1/2 tsp vanilla extract
- 1 cup powdered sugar
- 1/2 cup mini marshmallows
Instructions
For the brownies:
- Spread chopped walnuts on an ungreased sheet pan and bake at 350°F degrees for 6-8 minutes. Cool and store if not using right away.
- Preheat oven to 350°F. Grease an 8”x8” baking dish. In medium-sized saucepan, melt butter with cocoa powder over medium heat.
- Once butter has melted, remove saucepan from heat and add sugar, eggs, vanilla, flour, baking powder and salt.
- Stir in toasted walnut; pour into greased baking dish.
- Bake 20-25 minutes or until brownies begin to pull away from sides of pan. Cool pan completely on wire rack before frosting.
For the frosting:
- Combine all ingredients except for vanilla and powdered sugar in medium sized saucepan over medium heat.
- Bring to a full boil and cook 2 minutes, stirring occasionally.
- Remove from heat and stir in vanilla.
- Allow to cool to lukewarm, then add powdered sugar and whisk until smooth.
- Evenly spread marshmallows on top of cooled brownies; pour frosting evenly on top. Cut into squares.
Notes
- The walnuts can be toasted well in advance. Toasted nuts will keep sealed in an airtight container for about two weeks.
- You can use regular cocoa powder in this recipe instead of Dutch process; however, the chocolate flavor will not be as rich
- If frosting is too thick, thin it out with additional cream or half and half
- Once the powdered sugar has been mixed into the frosting, spread the frosting quickly before it sets up
- Brownies will keep in an airtight container for up to 3 days
- Brownies will freeze well if in an airtight container for up to 4 weeks