I'm Making These Retro Mud Hen Bars on Repeat

They’re packed with chocolatey, marshmallowy flavor.

By
Jessica Furniss
Jessica Furniss
Jessica Furniss
Jessica's food writing and photography have appeared in Food & Wine, MyRecipes, and on billboards. Currently, she specializes in creating how-to articles on baking and creative charcuterie boards for Simply Recipes, Allrecipes, and Southern Living. 
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Published September 17, 2025
Jessica Furniss
Stack of dessert bars with a meringue top and chocolate chips on a tabletop near a glass of milk

Simply Recipes / Jessica Furniss

I once scooped 200 cookies in 24 hours during recipe development because if I’m going to share a recipe with you, I want to make sure it’s the best version possible. But ever since the “day of 200 cookies,” I have a new respect for no-scoop cookie recipes.

Cookie bars are one of my favorite ways to get all the cookie flavor with none of the cookie work, so I’ve been making these easy, retro mud hen bars on repeat. 

These bars are the perfect dessert, but they also make a great addition to snack boards or a brunch spread. When I’m in the mood for an over-the-top dessert, I'll use mud hen bars as a base and top them with vanilla ice cream, chocolate syrup, and whipped cream for the most amazing sundae. 

What Are Mud Hen Bars?

You’ll find recipes for mud hen bars in recipe boxes and community cookbooks dating back about a century. While there’s no settled explanation for the unique name, “uglier than a mud hen” (a marsh bird with a mottled appearance) was a popular expression in the South in the early 20th century, and might relate to the brown, cracked appearance on the top of the bars. But don’t be fooled—while they might look plain on top, these bars pack tons of delicious flavor inside.

A chocolate chip cookie base is topped with marshmallows, pecans, and a chewy brown sugar meringue for the perfect sliceable cookie bar—no wrist cramps required! I love how the marshmallows and meringue combine with the buttery chocolate chip cookie base for a nod to the nostalgic flavor of s’mores.

And while the pecans add a really nice crunch, if you’re not a big fan of nuts in your desserts, you can leave them out and your mud hen bars will still be delicious. 

Sliced bar dessert with a cracked top and a serving spatula

Simply Recipes / Jessica Furniss

Tips for Making Mud Hen Bars

  • Don’t overmix the cookie base: When you add the flour and chocolate chips to the cookie dough, mix on low until just combined. If you overmix the cookie dough, the base will come out tough and dense.
  • Use a glass baking dish: Using a transparent vessel allows you to monitor how the cookie base is baking. If the cookie base looks gooey, it might be underdone. The base should look soft but not gooey when the bars are finished baking.
  • Dollop, then spread: The best way to add the meringue so it covers the marshmallows and pecans without pulling them up from the cookie base is to dollop all of the meringue into the center of the pan, then use a spatula to gently push the meringue to the edges. It’s okay if spreading the meringue pulls up a few pieces of the marshmallow and pecans here and there—just make sure the meringue covers the entire top of the dessert. 
  • Slice carefully: You can expect the meringue topping to crack when you slice into these mud hen bars, and that’s okay. Just slice carefully to keep as much of the meringue intact as possible, but don’t be afraid of the inevitable cracking.

Easy Tweaks

I love experimenting with different flavors of chips in the cookie base. Butterscotch chips or white chocolate chips both make for a creamier, sweeter bar. You can even double the amount of chocolate chips in the recipe for an extra-chocolatey cookie bar.

If you’re not a big fan of pecans, toasted walnuts work great in this recipe, too. Pistachios also work well, especially if you swap out the chocolate chips for white chocolate chips. 

Dessert bars with a meringue top and visible chocolate chips

Simply Recipes / Jessica Furniss

More Cookie Bar Recipes To Try

Mud Hen Bars

Prep Time 30 mins
Cook Time 30 mins
Cooling Time: 60 mins
Total Time 2 hrs
Servings 12 servings
Yield 12 bars
Cook Mode (Keep screen awake)

Ingredients

  • Nonstick cooking spray

  • 3 large eggs, divided

  • 8 tablespoons (1 stick) unsalted butter, softened

  • 1/2 cup (100g) granulated sugar

  • 2 teaspoons vanilla extract

  • 1 1/2 cups (180g) all-purpose flour

  • 2/3 cup bittersweet or semisweet chocolate chips

  • 1 teaspoon baking powder

  • 1/2 teaspoon salt

  • 1 cup miniature marshmallows

  • 1/2 cup chopped pecans, toasted, optional

  • 1 cup (213g) packed brown sugar

Method

  1. Preheat the oven to 350°F.

    Spray a 9x13-inch glass baking dish with nonstick cooking spray.

  2. Make the cookie base:

    Separate two of the eggs, leaving the last one whole, and set aside. Add the softened butter to the bowl of a stand mixer fitted with the paddle attachment or a large bowl if using a hand mixer. Beat on high speed for 30 seconds. Add the granulated sugar and beat on high until light and fluffy, about 2 minutes. 

    Add the whole egg, the two egg yolks, and the vanilla extract and beat on high until smooth, about 1 minute. Stop the mixer and add the flour, chocolate chips, baking powder, and salt. Beat on low speed until just combined, about 30 seconds.

  3. Assemble the base and filling:

    Use a spatula to spread the cookie dough evenly into the prepared baking dish. Sprinkle the marshmallows and pecans evenly over the cookie base.

    Cookie dough pressed into rectangular glass baking dish for mud hen bars recipe

    Simply Recipes / Jessica Furniss
    Cookie dough in square glass balking dish topped with mini marshmallows and chopped pecans for mud hen bars recipe

    Simply Recipes / Jessica Furniss
  4. Make the meringue:

    Wash and thoroughly dry the mixer bowl. Add the remaining two egg whites and beat with the whisk attachment on medium-high speed until they start to get frothy, about 2 minutes. Add the brown sugar and beat on medium-high again until stiff, glossy peaks form, about 7 minutes.

  5. Spread the meringue:

    Use a spatula to dollop the meringue into the center of the baking dish, then gently spread it over the marshmallows and pecans, being sure to cover the entire dessert.

    Egg white mixture for meringue getting spread over cookie dough base in a baking dish with a gray spatula for mud hen bars recipe

    Simply Recipes / Jessica Furniss
    Cookie dough topped with evenly spread out meringue mixture in a rectangular glass baking dish for mud hen bars recipe

    Simply Recipes / Jessica Furniss
  6. Bake:

    Bake until the meringue is a deep golden brown and the cookie base no longer looks gooey, about 30 minutes.

  7. Cool and slice:

    Allow the dessert to cool completely, 1 to 2 hours, before slicing into bars.

    Store completely cooled bars in an airtight container at room temperature for up to 2 days or freeze for up to 2 months.

    Love the recipe? Leave us stars and a comment below!

    Rectangular glass baking dish with meringue topped cookie dough cut into squares for mud hen bars recipe

    Simply Recipes / Jessica Furniss
Nutrition Facts (per serving)
302 Calories
12g Fat
47g Carbs
4g Protein
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Nutrition Facts
Servings: 12
Amount per serving
Calories 302
% Daily Value*
Total Fat 12g 15%
Saturated Fat 7g 35%
Cholesterol 67mg 22%
Sodium 157mg 7%
Total Carbohydrate 47g 17%
Dietary Fiber 1g 4%
Total Sugars 33g
Protein 4g
Vitamin C 0mg 0%
Calcium 52mg 4%
Iron 1mg 8%
Potassium 96mg 2%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
Nutrition information is calculated using an ingredient database and should be considered an estimate. In cases where multiple ingredient alternatives are given, the first listed is calculated for nutrition. Garnishes and optional ingredients are not included.