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Mississippi Mud Cookies

The classic Southern potluck cake turned into a big, fudgy cookie. A brownie mix shortcut makes the dough easy, then each cookie gets toasted marshmallows, pecans, and a drizzle of homemade chocolate icing.
Prep Time 20 minutes
Cook Time 12 minutes
Chill & Cool Time 50 minutes
Total Time 1 hour 22 minutes
Serving Size 16 cookies

Ingredients

Cookies

  • 1 box brownie mix about 18 oz, plain (not the kind with a fudge packet)
  • 2 large eggs
  • 1/4 cup vegetable oil
  • 1 cup semisweet mini chocolate chips
  • 1/2 cup pecans rough chopped, optional
  • 1 1/2 cups mini marshmallows

Chocolate Icing

  • 1/2 cup butter softened (8 tablespoons)
  • 3 cups powdered sugar
  • 4 tablespoons cocoa powder heaping
  • 1 teaspoon vanilla extract
  • 6 tablespoons milk add a little at a time, as needed

Instructions

Cookies

  • In a large bowl, add the brownie mix, oil, and eggs (one at a time). Stir with a scraper or wooden spoon until no dry pockets remain. The dough will be thick.
  • Stir in the mini chocolate chips. If you want pecans inside every cookie, stir them in now.
  • Scoop generous, overflowing balls of dough onto a lined baking sheet, leaving room to spread. Do not flatten.
  • Chill the tray in the refrigerator for 20 minutes. Meanwhile, preheat the oven to 350°F.
  • Bake 10 to 12 minutes, until the edges are set and the centers are still slightly soft.
  • Press a few marshmallows onto each cookie. Sprinkle pecans between the marshmallows on any cookies you want with nuts.
  • Return to the oven for 1 minute, just until the marshmallows puff and barely start to brown. Cool completely.

Chocolate Icing

  • Microwave the softened butter 8 to 10 seconds, just until it barely begins to melt.
  • Add the powdered sugar, cocoa powder, vanilla, and half the milk. Whisk, adding more milk 1 tablespoon at a time until smooth.
  • If the icing is too thick to drizzle, microwave 10 to 12 seconds and whisk again until pourable.
  • Drizzle the icing over the cooled cookies with a spoon. Let it set before serving.

Notes

  • Brownie mix: Use a plain 18 oz brownie mix. Skip mixes that include a separate fudge packet.
  • Scoop first: Scoop the dough before chilling. It is much harder to scoop once cold.
  • Nut-free option: Add pecans on top after baking so you can leave some cookies plain. Keep the pecan cookies separate from the nut-free ones.
  • Full batch of icing: These icing amounts are a full batch. A half batch covers only about 8 cookies.
  • Thinner drizzle: Warm the icing a few seconds longer so it runs in thin streams and goes farther.
  • Size: These are rich. Make them smaller if you like and reduce the bake time slightly.
  • Storage: Store in an airtight container at room temperature up to 3 days, or freeze once the icing is set.