Brown Butter Mud Hen Cookie Bars

 A layered cookie bar with quite a name, but quite an amazing lineup. Think chocolate chip cookie bar topped with more chocolate, pecans, marshmallows, and a crackly brown sugar meringue. It's decadent, crisp, & chewy - all in one. One bite, and you're hooked.

I can't remember when I first discovered these bars. It was at least 6 or 7 years ago when I ran across a recipe somewhere on the internet, and I randomly decided to make them. I was blown away by how delicious and unique they were. I've never seen another cookie bar like this since, and it's so special. They're spectacular.

They are relatively easy to pull together, and you'll be surprised by how much your friends and family will love them. I brought them to Sunday lunch with my family, and they were disappearing as fast as I could sit them out. True story.

Luckily, these bars are made with ingredients typically found in most pantries. If you're needing a dessert to take to a work event, church meal, family potluck, or birthday party - here you go. Mud Hen Bars are about to be your newest best friend.

Ingredients Needed for Brown Butter Mud Hen Bars

- unsalted butter

- light brown sugar

- milk

- vanilla extract

- large eggs

- cornstarch

- all purpose flour

- baking powder

- kosher salt

- mini semi sweet chocolate chips

- dark chocolate chips

- mini marshmallows

- pecans, chopped

Other Add-Ins

Feel free to swap the mini chocolate chips, dark chocolate chips, and pecans out for something else. In my opinion, the marshmallows are sort of nonnegotiable, but do whatever floats your boat! Consider these options for your Mud Hen Bars:

- white chocolate chips

- milk chocolate chips

- peanut butter chips

- butterscotch chips

- caramel bits

- peanut butter cups, chopped

- m&m candies

- pistachios, chopped

- macadamia nuts, chopped

- crushed pretzels

- toasted coconut


How to Make Brown Butter Mud Hen Bars

Cookie Base:

1. Preheat the oven to 350°F. Grease and line a 9x13 baking dish with parchment paper and leave an overhang to allow for easy removal.

2. In a small saucepan over medium heat, melt the butter. Cook, stirring occasionally, until the butter turns a deeper golden in color and has a nutty smell, about 5 minutes. Remove from heat and allow to cool to room temperature and firm to a point that it is no longer liquid. (I add a small ice cube to the butter to help the cooling process and add back a little moisture.)

3. In a large mixing bowl or base of a stand mixer, beat together cooled browned butter, 1/2 cup brown sugar, and granulated sugar until light and fluffy, about 2 minutes. Mix in the milk, vanilla extract, 1 egg, and 2 egg yolks (set whites aside for the meringue). Continue to beat until mixture is smooth and begins to lighten in color, about 3 minutes.

4. In a small bowl, whisk together cornstarch, flour, baking soda, and salt. Gradually beat into wet ingredients until combined. Stir in the mini chocolate chips.

Assembly & Baking:

5. Spread cookie mixture evenly into bottom of the prepared pan. You may use your hands or a spatula to gently pat the cookie dough into the corners of the pan.

6. Sprinkle dark chocolate chips, marshmallows, and pecans evenly over cookie layer.

7. In a small bowl, using an electric mixer with a whisk attachment, beat egg whites on high until stiff peaks form, about 3 minutes.

8. Fold remaining 1 cup of light brown sugar into egg whites until combined. Spread evenly over chocolate chips, marshmallows, and pecans.

9. Bake for 30-32 minutes, or until meringue begins to brown and cookie is just set. Remove from oven and allow to cool completely before removing from the pan and slicing into squares. Enjoy! (Store leftovers in an airtight container at room temperature for up to 5 days or in the freezer for up to 3 months.

Make It Gluten Free

To make these bars gluten free, skip the cornstarch and simply use 1 ½ cups of gluten free flour and ¾ teaspoon xanthan gum. However, if your gf flour blend already contains xanthan gum, skip the extra addition.

Essentials for Making Brown Butter Mud Hen Bars

a rubber spatula: here's my very favorite one. I have it in many colors, and I've never found a better spatula. Worth. Every. Penny.

- all of the GIR spatulas are my go-to kitchen tool

whisk set: sizes for all jobs & tasks

favorite 9x13 baking pan: I love the straight sides

parchment paper sheets

glass mixing bowl set: for mixing together all the ingredients

- nesting plastic mixing bowl set: I love using these to mix together the dry ingredients and even the meringue

my favorite hand mixer

- favorite serrated knife: for cutting the bars

- my favorite cutting boards: they are antibacterial, don't warp, and are dishwasher safe. Plus, they don't dull knives, unlike plastic cutting boards.

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Looking for desserts to try?

Cookies, cookies, & cookies:

Coffee Cake Cookies (gluten free or regular)

The Ultimate Kitchen Sink Cookies (gluten free or regular)

- Gingerbread Crinkle Cookies (gluten free or regular)

Bourbon Chocolate Cherry Cookies (gluten free or regular)

Classic Oatmeal Cream Pies (gluten free or regular)

Other sweet treats to create:

- Chocolate Lava Cakes for Two (gluten free or regular)

Made the recipe?

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