Mississippi Mud Pie Brownies
Meet your new epic signature batch of brownies that will have everyone talking: Mud Pie Brownies! Easy homemade brownies are loaded with chopped chocolate, baked to fudgy perfection, and then topped with mini marshmallows and a decadent drizzle of chocolate icing!
The Best Gooey Brownie You’ll Ever Eat!
Wondering how to make a chocolaty fudgy brownie even better? Smother it in a layer of toasted marshmallows and then drizzle it with chocolate icing! Trust me, these brownies are pure indulgence!
Every bite is a mouthful of delicious texture from the fudgy brownie to the gooey, sticky marshmallow. The explosion of flavor and texture combines for a dessert that just melts in your mouth!
The secret to this culinary brilliance is found in the brownies. Though they’re made with ordinary baking ingredients, we use a one-pot technique where the butter and sugar are melted together instead of being creamed like most recipes call for. This elimination of air delivers a perfectly chewy, fudgy brownie that makes for the very BEST base in these Mud Pie Brownies!
Rebecca’s Recipe Review
Taste: Deeply chocolaty brownies topped with soft and gooey marshmallows and a sugary boiled chocolate icing.
Texture: Sticky, fudgy, and soft.
Ease: 6/10
Pros: Simple but impressive in looks and flavor!
Cons: Sticky kid fingers after enjoying 😂
Would I Make This Again? Oh yes, they’re perfect for just about any time of year!
Mississippi Mud Pie Brownie Ingredients
The foundation of these decadent brownies is my Recipe For Chocolate Fudge Brownies, which is made with pantry staples such as granulated sugar, canola oil, vanilla extract, all-purpose flour, Dutch-process cocoa powder, salt, and of course, a chopped-up dark or milk chocolate bar.
Completing the brownie batter is unsalted butter and large eggs. When it comes to butter, I reach for a European-style butter such as Kerrygold or Finlandia. Since European-style butter has a higher fat content, it produces a richer flavor in these brownies, making them absolutely mouthwatering!
To give these brownies their signature mud pie flavor, they’re covered in mini marshmallows and a 5-ingredient homemade chocolate icing. To make the icing, you’ll need salted butter, powdered sugar, unsweetened cocoa powder, whole milk, and vanilla extract.
How To Make Mississippi Mud Pie Brownies
- Preheat the oven and line a cake pan with parchment paper and then lightly spray it with nonstick cooking spray.
- Melt unsalted butter over low heat and then stir in granulated sugar until the mixture becomes smooth. Remove the pot from the stove and allow it to cool, stirring often to release heat.
- Beat canola oil and vanilla extract into the butter and sugar mixture until fully combined with no separation between the ingredients.
- Add the large eggs in one at a time, beating each one with a spatula or fork after each addition.
- Sift all-purpose flour, Dutch-process cocoa powder, and salt into the butter and sugar mixture. Mixing until the dry streaks are gone.
- Fold a portion of the dark or milk chocolate into the brownie batter.
- Pour the brownie batter into the prepared baking pan and then sprinkle the remaining chocolate chunks on top.
- Bake the brownies in the preheated oven until done. Then remove them from the oven and evenly sprinkle mini marshmallows over the top of the brownies. Afterward, transfer the marshmallow covered brownies back into the oven to bake.
- Remove the brownies from the oven and then allow them to cool while preparing the icing.
- Prepare the icing by melting salted butter over medium heat.
- Sift powdered sugar and unsweetened cocoa powder into the melted butter. Whisk until combined and then pour in the whole milk and vanilla extract.
- Remove the icing from the heat and immediately pour it over the top of the mini marshmallows. Spreading it as evenly as possible before the icing sets.
- Allow the iced brownies to set completely before removing the batch from the pan to slice into squares.
Rebecca’s Tips
- Be sure to prepare the pan well so the brownies can be easily removed with as minimal a mess as possible. Layering the pan with parchment paper may require two sheets, one going in each direction, allowing some to hang over the edges so you can grip it to remove them once they’re cooled.
- If you prefer, you can use chocolate chips in place of chocolate chunks from the chopped chocolate bars.
- For a rocky road version, you can mix almonds, walnuts, or pecans into the brownie batter.
- The easiest and cleanest way to slice these brownies into squares is to use a plastic knife. I found that the marshmallows stuck to a metal chef’s knife unless it was sprayed with nonstick spray and wiped clean between each slice.
Storage Instructions For Mississippi Mud Pie Brownies
If you aren’t planning to eat these brownies the same day, I’d recommend leaving them in the pan and covering it tightly with plastic wrap or aluminum foil. Not slicing into the Mud Pie Brownies until you’re ready to serve them will preserve their freshness and protect their texture.
Once sliced, transfer the squares into an airtight container. If you need to layer the brownies in the storage container, then I’d recommend separating the layers with parchment paper to prevent them from sticking together.
Store the Mud Pie Brownies in an airtight container at room temperature to enjoy for up to 3 days.
How To Serve Mississippi Mud Pie Brownies
These Mud Pie Brownies are a delicious dessert as is, but for an extra gooey treat, you can pop slices in the microwave before enjoying them! Want to take things a step further?
Top your warm mud pie brownie with a scoop of vanilla ice cream or a dollop of whipped cream!
More Brownie Recipes
- Homemade Brownie Bites – The perfect bite-sized treat, great for parties!
- Brownie Cookies – Made from an adapted boxed brownie mix for an easy treat!
- Walnut Fudge Brownies – Fudgy brownies loaded with crunchy toasted walnuts!
- Coffee Brownies – An ultra-rich, chocolaty coffee dessert that coffee lovers will devour!
- Twix Caramel Brownies – Baked with Twix candy bars and drizzled with caramel!
Did You Make This Recipe?
If you’ve tried this recipe, please let leave a review in the comments below. I love hearing from you! Don’t forget to tag me – @sugarandsoulco – on Instagram and Pinterest with your photos, or join our Sugar & Soul Show-offs Community and share them there.
This recipe was originally published in November 2015 and was updated in September 2025 with a newly tested and improved recipe and photos. The original used a box brownie mix and marshmallow fluff.
Mississippi Mud Pie Brownies
Ingredients
Brownies
- 1 cup unsalted butter 227g, I use Kerrygold
- 2½ cups granulated sugar 500g, I use Domino
- 2 tablespoons canola oil
- 1 tablespoon vanilla extract
- 5 large eggs I use Vital Farms
- 1 cup all-purpose flour 130g, I use King Arthur
- ¾ cup + 1 tablespoon Dutch-process cocoa powder 80g, I use Ghirardelli
- ¾ teaspoon salt
- 8 ounces dark or milk chocolate I like using half a Trader Joe's Pound of Chocolate bar
Topping
- 6 cups mini marshmallows 270g
- 6 tablespoons salted butter 84g
- 2½ cups powdered sugar 288g
- 2 tablespoons unsweetened cocoa powder
- ¼ cup whole milk
- 2 teaspoons vanilla extract
Instructions
- Preheat oven to 350°F and line a metal 9×13-inch cake pan with parchment paper and spray lightly with cooking spray. Make sure some of the parchment is over the edge of the pan for easy removal. This may require two sheets, one going in each direction – make sure the one that goes across the shorter distance is under the one that goes along the full length of the pan.
- Melt 1 cup unsalted butter in a heavy-bottomed saucepan over low heat. Add 2½ cups granulated sugar and stir until smooth, the butter and sugar have started emulsifying, and no butter is separated from the sugar. Remove from heat and let the mixture cool for 5 minutes, stirring often to release heat.
- Add 2 tablespoons canola oil and 1 tablespoon vanilla extract to the butter and sugar and beat them in with a rubber spatula until fully combined and there's no separation between the ingredients (no oil resting on top).
- Beat in 5 large eggs one at a time, beating with the spatula or a fork after each one. Mix until fully incorporated.
- Sift 1 cup all-purpose flour, ¾ cup + 1 tablespoon Dutch-process cocoa powder, and ¾ teaspoon salt into the butter and sugar mixture, stirring gently with a rubber spatula just until the dry streaks are gone.
- Fold most of the 8 ounces dark or milk chocolate into the batter.
- Pour the brownie batter into the prepared baking pan, sprinkle the remaining chunks on top, and bake for 25 minutes.
- Pull the brownies out of the oven and evenly sprinkle 6 cups mini marshmallows over the top of the brownies, and put them back in the oven to bake for an additional 3 minutes.
- Remove the brownies from the oven and allow to cool for a few minutes while the icing is prepared.
- Prepare the icing by melting 6 tablespoons salted butter in a saucepan over medium heat.
- Sift in 2½ cups powdered sugar and 2 tablespoons unsweetened cocoa powder and whisk until combined, then whisk in ¼ cup whole milk and 2 teaspoons vanilla extract.
- Remove from heat and immediately pour over the top of the mini marshmallows, using a rubber spatula to help cover as evenly as possible. The icing will begin to set quickly.
- Let the icing set completely before removing the brownies from the pan and slicing into squares for best results. Use a plastic knife for the cleanest cuts. The marshmallows will stick to a metal chef's knife unless it's been sprayed with nonstick spray and wiped down.
Notes
- Thicker chocolate bars are preferred for this recipe, so you have big chunks about the size of a penny. However, thinner baking chocolate, like Ghirardelli, can be used, as well as prepackaged chocolate chunks (although these usually tend to have additional ingredients added, which can impact the flavor).
- Chocolate chips may also be used.
- It’s important to add the marshmallows and bake for a couple of additional minutes to help the marshmallows expand slightly and stick to the brownies.
Nutrition
Did You Make This Recipe?
Don’t forget to share it with me on Instagram @sugarandsoulco and follow on Tiktok @sugarandsoulco and Pinterest @sugarandsoulco for more!
Share your thoughts!
Love this recipe? Share your thoughts with me and leave a review! And don’t forget to connect on your favorite social platform below!
Made this for dessert tonight and it was fantastic!! Thanks for sharing your recipe!!!
I’m so glad your family enjoyed it, Lisa!
These look like they might be the best thing ever! As I huge supporter of boxed brownies I fully approve of these and that topping looks incredible! !
Right! I LOVE boxed brownies and adore dressing them up a bit!
I love that you slid them under the broiler to get the fluff toasty – they look absolutely delicious and addictive. I think I’ll have to make a batch this weekend.