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About This Recipe
Okay, guys. We have FINALLY reached the end of my top 5 count down of my FAVORITE recipes in the new Sweets (Cookies, Brownies, Blondies, and Bars) cookbook!
We have already drooled over the Cake Batter Oreo Blondies, Frosted Sugar Cookie Bars, Healthier Seven Layer Magic Bars, and the Carrot Cake Blondies. And now here we are, drooling over MY NUMBER ONE FAVORITE recipe in the cookbook. THESE MISSISSIPPI MUD BROWNIES! 😍
I wish I could accurately describe just how epic these brownies are, but no words seem to do them justice!
On their own, the brownies are perfectly fudgy and moist…but layered with gooey, melty marshmallows and the most amazingly rich chocolate frosting? It’s hard NOT to fall in love with these brownies!
Mississippi Mud Brownies can seem intimidating because they have three layers. But I want to stress just how EASY these are to make!
The brownies require only one bowl. Once they’re done, you top them with marshmallows and then frosting. This brownie, marshmallow, and chocolate frosting combo will make your taste buds dance like they’ve never danced before! Healthy, easy, and delicious, you’ve GOT to try them!
Why You’ll Love These Mississippi Mud Brownies
- So incredibly gooey and melt in your mouth good!
- Made with sweet and melty vanilla marshmallows and the best chocolate frosting you ever did have!
- Brownies + marshmallows + chocolate = THE MOST EPIC COMBINATION EVER! I mean, come on! 😍
- Lower in calories than your traditional chocolate brownie and have a punch of protein.
- No one will ever guess that these brownies have been healthified. 😉
- Have I mentioned they’re delicious? Because they’re freaking delicious, y’all!!!
- Protein powder – I used PEScience Gourmet Vanilla. A chocolate flavor would also work great. Not all protein powders bake the same, so if you use another brand, just make sure it is also a whey+casein blend and one that bakes well. For all PEScience products, you can save 10% off your purchase with my affiliate code Laurenfitfoodie.
- Oat flour – I like the flavor oat flour brings, but all-purpose flour, 1:1 gluten-free flour, and whole wheat flour should work as good substitutes. If you don’t have oat flour, you can also blend quick oats in a blender until it reaches a flour consistency. I haven’t tried the brownie part of this recipe with almond or coconut flour, so I can’t speak on those. If do try, let me know how your brownies turn out in the comments!
- Cocoa Powder – I used dark cocoa powder. I think this recipe tastes fudgier with black cocoa or dark cocoa powder, but if all you have is normal cocoa powder, you can use that.
- Sweetener – I used Swerve Granular sweetener. You could also use erythritol, Splenda, stevia, normal sugar, or any other sweetener of choice.
- Baking essentials – Baking powder and baking soda.
- Canned pumpkin – Libby’s brand is my favorite. It produces the best texture.
- Light butter – I used I Can’t Believe It’s Not Butter Light.
- Milk – I used unsweetened almond milk. Any milk will work here!
- Chocolate chips – Or any chips you fancy!
- Mini Marshmallows – So sweet and gooey! The perfect topping for these brownies.
- Nut Butter – used to make the chocolate frosting. I used American Dream Nut Butter (code Laurenfitfoodie saves you 10%), but any kind will do. The drippier, the better!
- Sugar-free pancake syrup – You can replace with maple syrup or another sticky syrup if you wish.
How To Make
- Preheat the oven to 325°F. Line a 8×8-inch baking pan with parchment paper and/or spray with nonstick cooking spray.
- In a large bowl, add protein powder, oat flour, cocoa powder, sweetener, baking powder, and baking soda. Stir dry ingredients until they are mixed well. Then, add pumpkin, butter, milk, and melted chocolate. Using a hand (or stand) mixer, mix to combine. Pour the batter into the prepared dish.
- Bake for 18-20 minutes or until a toothpick inserted in the center comes out mostly clean. Be careful not to over-bake! You want to take them out right before they are done so they have a gooier texture.
- While the brownies are baking, make the chocolate frosting. Add all of the frosting ingredients together and beat until smooth. Set aside.
- Remove the brownies from the oven and immediately top with the marshmallows. Turn the oven off. Then, add the brownies with the marshmallows back in the oven for 5-6 minutes or until desired gooiness.
- To frost, scoop dollops of chocolate frosting over the soft marshmallows while the brownies are still hot. Then, gently spread or nudge the dollops of frosting around to touch each other. It won’t be perfect because the soft marshmallows make it tricky to truly “frost” the brownies, but it will be okay if marshmallows poke through in places. Frosting these brownies while they are still warm helps because the frosting will melt just a bit and make for extra gooey yumminess.
- Enjoy these brownies warm or put them in the refrigerator overnight. I personally prefer to let them set in the fridge overnight. This lets the flavors come together more!
Tips For The Best Brownies
- Use the ingredients called for in the recipe. I know, I know. Sometimes you need to substitute something in a crunch. But just remember, baking is a science! And using different ingredients can result in different flavors and textures, especially when protein powder is involved. So, for best results, try to match the ingredients as best as you can.
- Don’t over-bake. These brownies actually still bake some when you remove them from the oven. I recommend taking them out when the edges are set and a toothpick inserted in the center comes out mostly clean. This will result in the most gooey texture! Baking until the toothpick comes out totally clean will result in a more cakey brownie, which is not what we’re going for.
- Let chill over night. For the best results, make the brownies and let them sit in the fridge overnight. They are good when you frost them after they’ve cooled off from the oven, but I promise you they are 10x better when they are chilled and the flavors have had time to come together.
Do I need to use oat flour in this recipe?
No, you don’t. All-purpose flour and 1:1 gluten-free flour will work great.
Can I freeze these brownies?
Yes, these brownies do freeze well. Just cut the brownies, wrap individually in aluminum foil, and store in an air tight freezer safe Ziploc bag. They will stay fresh for 3 months.
Can I leave out the protein powder?
You most certainly can. If you don’t want to add protein, you still need to maintain a similar wet/dry ratio of ingredients. So, just replace with the same amount of flour. One scoop of protein powder is about 1/4 cup of flour.
- 1/2 cup chocolate or vanilla protein powder (62g)
- 1/4 cup oat flour (30g)
- 1/3 cup cocoa powder (40g)
- 1/4 cup Swerve granular sweetener (48g)
- 1/2 tsp baking powder
- 1/4 tsp baking soda
- 1 cup canned pumpkin (244g)
- 2 Tbsp light butter (28g) softened
- 2 Tbsp unsweetened almond milk (30g)
- 2 Tbsp semi-sweet chocolate chips (30g) melted
- 1.5 cups mini marshmallows (142g)
- 2 Tbsp cocoa powder (10g)
- 2 Tbsp chocolate or vanilla protein powder (15g)
- 1/4 cup almond or peanut butter (56g) drippy is best
- 1/4 cup sugar-free pancake syrup (60g)
- 2 Tbsp unsweetened almond milk (30g)
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- Preheat the oven to 325 degrees F. Line a 8×8-inch baking pan with parchment paper and/or spray with nonstick cooking spray.
For the Brownies:
- In a medium-sized bowl, add the protein powder, flour, cocoa powder, sweetener, baking powder and baking soda. Stir dry ingredients until they are mixed well. Then add the pumpkin, butter, milk and melted chocolate. Using a hand mixer, mix to combine. Pour the batter into the prepared dish.
- Bake for 18-20 minutes, or until a toothpick inserted in the center comes out mostly clean.
For the Marshmallow Layer:
- Remove the brownies from the oven and immediately top with the marshmallows. Cut the oven off, then add the brownies with the marshmallows back in the oven for 5-6 minutes.
For the Frosting:
- While the brownies are baking, mix all of the frosting ingredients together and beat until smooth. Set aside.
- To frost, scoop dollops of frosting over the soft marshmallows while the brownies are still hot and then gently spread or nudge the dollops of frosting around to touch each other. It won’t be perfect because the soft marshmallows make it tricky to truly "frost" the brownies, but it will be okay if marshmallows poke through in places. Frosting these brownies while they are still warm helps because the frosting will melt just a bit and make for extra gooey yumminess.
- Let brownies cool in the pan for 15 minutes. If you wish to eat warm, cut into bars. If you prefer them cold, go ahead and store them in the fridge, covered, and cut into bars when you are ready to eat. They will be easier to cut the longer they have set.
Nutrition is hand-calculated and accurate. No autocalulations! However, note that values can vary based on the brands you use and if you substitute ingredients.