Gooey Mississippi Mud Brookies
These Gooey Mississippi Mud Pie Brookies are layers of fudge chocolate brownie and chocolate chip cookies mixed with pecans and mini marshmallows.

- Prep time
- 15 min
- Cook time
- 25 min
- Yield
- 12 servings
- Difficulty
- HARD
Ingredients
- 1 Box brownie mix
- Ingredients on the box (oil, eggs water)
- 1+1/2 cup mini marshmallows, divided
- 1 cup chopped pecans, divided
- 1/2 cup (1 stick) unsalted butter
- 1/2 cup light brown sugar, packed
- 1/2 cup granulated sugar
- 1 Large egg
- 2 tsp pure vanilla extract
- 13/4 cup all-purpose flour
- 1/2 tsp salt
- 1/2 tsp baking soda
- 3/4 cup mini chocolate chips
Instructions
- 1
Preheat oven to 350°F
- 2
In a medium sized bowl, combine brownie mix, egg, vegetable oil and water according to the instructions on the box. Beat until thoroughly mixed.
- 3
Line a 9×13” pan with parchment paper or a baking mat. Pour the brownie batter over the baking mat and spread evenly.
- 4
Sprinkle the top of the batter with ½ cup crushed pecans and ¾ cup of mini marshmallows and gently press into the brownie batter.
- 5
Soften the butter in the microwave for 10-15 seconds. Combine the butter with both light brown sugar and granulated sugar. Mix until smooth and the mixture becomes fluffy.
- 6
Add the egg and vanilla extract and beat until the egg is thoroughly incorporated.
- 7
In a separate bowl, combine the flour, salt and baking soda. Slowly add the flour mixture to dough batter while mixing at a low speed. Once all the flour has been added, increase speed to medium until dough forms. Add chocolate chips, remaining pecans and marshmallows last and fold into cookie dough.
- 8
Take the cookie dough and drop chunks onto the top of the brownie mixture, gently pressing them down into brownie batter. Do you best to cover evenly.
- 9
Bake for 25-28 minutes at 350°F. Remove from oven and allow to cool completely before cutting. Since I used a baking mat, I was able to completely remove the sheet of brookies from the pan before cutting. If the brownie is still too gooey, I suggest refrigerating before cutting.