Mississippi Mud Bars on a plate with milk.

If you’ve never had one of these Mississippi Mud Bars, you’re in for a treat. A firm cookie layer, topped with nuts, chocolate chips and marshmallows, and then covered in a unique meringue flavored with brown sugar, these treats are the essence of Southern decadence. The crust is supposed to resemble mud drying and cracking in the sun!

The interesting and unusual thing about these bars is the topping – a thin, crispy, sweetened crust made from meringue and brown sugar. Some people fret about making meringue, but this is the perfect treat to learn how to do it.

First of all, you already have the whites from the separated yolks, so there is no waste (hooray!) And you’re folding in sugar into the beaten whites, so you don’t have to get the meringue completely perfect. It’s going to get a bit flattened anyway with the folding.

How to Make a Meringue

Meringue is just beaten egg whites – the trick is knowing when to stop.

Usually in a recipe you’ll see “soft peak” and “stiff peak” when describing what type of meringue they want. A soft peak is a meringue with small, fine uniform bubbles, but when you pull the beaters out, it gently falls back to . . . well, soft peaks. “Stiff peak” on the other hand will form sharp, pointy peaks when you pull out the beaters.

What you want to avoid is the curdled meringue – where you’ve gone too far.

Here’s a great video that shows you what I’m talking about:

I prefer to use a hand mixer for beating egg whites. I just have more control than with my big stand mixer. And when beating just two eggs – well, I’m not even sure it would work. If you need a good hand mixer, here’s a great one from Amazon:

Print Recipe

5 from 1 vote

Mississippi Mud Bars

If you've never had one of these Mississippi Mud Bars, you're in for a treat. A firm cookie layer, topped with nuts, chocolate chips and marshmallows, and then covered in a unique meringue flavored with brown sugar, these treats are the essence of Southern decadence.

Prep Time15

Cook Time35

Total Time50

Course: Cookies

Cuisine: American

Keyword: Mississippi Mud Bars

Servings: 36 Bars

Calories: 180kcal

Author: Don Herman

Ingredients

1/2 Cup Butter
1 Cup Granulated Sugar
2 lg Eggs separated and reserved
1 1/2 Cup All-Purpose Flour
1 tsp Baking Powder
1/2 tsp Salt
1 Cup Chopped Walnuts
1/2 Cup Semisweet Chocolate Chips
1 Cup Miniature Marshmallows
1 Cup Brown Sugar dark, firmly packet

Instructions

Preheat oven to 350° F
Line a 13 X 9" baking pan with parchment, so that the parchment drapes over the side by about 1". This will be a handle for you to lift out the bars.
Whisk together the flour, baking powder and salt. Set aside.
Cream together the butter and sugar until light and fluffy – about 3 minutes on medium. Beat in the egg yolks, one at a time, just until blended.
On the lowest speed, fold in the flour mixture until all is uniformly moistened.
Press the mixture into the prepared baking pan and pack down firmly. Sprinkle the nuts, chips and marshmallows over the top of the mixture in the pan.
In a large bowl, beat the egg whites until stiff peaks form. With a spatula, fold in the brown sugar, trying to keep as much air in the whites as possible. Spread over the mixture in the pan.
Bake for 35 minutes or until a crust is formed. Remove from oven and let cool in the pan for 5 minutes, then remove to a rack to cool completely.
Cut into squares and serve.

Notes

Don’t stress too much about the egg whites. You’ll be folding in brown sugar, which is going to collapse them quite a bit anyway.

Try my other sweet treats, like Easy Homemade Brownies or Dark Chocolate Pistachio Cookies! And let me know how you enjoyed the bars by leaving a note below.