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Mississippi Mud Cake Brownies

Rich, gooey, and nutty chocolate brownies topped with fluffy marshmallows, perfect for any occasion.
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Prep Time 15 minutes
Cook Time 30 minutes
Total Time 45 minutes
Servings: 12 pieces
Course: Dessert, Snack
Cuisine: American
Calories: 350
Ingredients Method Notes

Ingredients
  

For the brownies
  • 1 cup butter Use unsalted butter so you control the salt.
  • 2 cups granulated sugar
  • 4 large eggs
  • 1 teaspoon vanilla extract
  • 1/3 cup unsweetened cocoa powder
  • 1 1/2 cups all-purpose flour
  • 1/4 teaspoon salt
  • 1 cup chopped pecans Toast lightly for extra crunch and aroma.
For the marshmallow topping
  • 4 cups mini marshmallows Fresh mini marshmallows puff best; stale ones won’t melt the same.
For the frosting
  • 1/2 cup butter
  • 1/3 cup unsweetened cocoa powder
  • 1/3 cup milk
  • 1 teaspoon vanilla extract for frosting
  • 3 1/2 cups powdered sugar

Method
 

Preparation
  1. Preheat oven to 350°F (175°C). Grease a 9x13-inch baking dish.
  2. In a large bowl, melt 1 cup butter until glossy. Stir in 2 cups granulated sugar.
  3. Add 4 large eggs and 1 teaspoon vanilla extract. Beat until smooth and shiny.
  4. Stir in 1/3 cup unsweetened cocoa powder, 1 1/2 cups all-purpose flour, and 1/4 teaspoon salt. Mix until smooth.
  5. Fold in 1 cup chopped pecans. Pour the batter into the prepared pan and smooth the top.
Baking
  1. Bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean.
  2. Remove the brownies from the oven. Immediately sprinkle 4 cups mini marshmallows evenly over the top.
  3. Return to the oven for 5 minutes, until marshmallows puff and get slightly golden.
Frosting
  1. While the marshmallows puff, melt 1/2 cup butter in a medium saucepan. Stir in 1/3 cup cocoa powder and 1/3 cup milk until smooth.
  2. Remove from heat and stir in 1 teaspoon vanilla extract. Gradually whisk in 3 1/2 cups powdered sugar until silky and pourable.
  3. Remove the brownies from the oven and pour the warm frosting evenly over the marshmallows. Spread gently with a spatula.
  4. Let the pan cool completely before cutting so the frosting sets and the marshmallow layer settles.

Notes

For best flavor, serve warm with a scoop of vanilla ice cream. Store at room temperature in an airtight container for up to 3 days, or refrigerate for up to a week. To freeze, wrap squares tightly and freeze for up to 2 months.