Brownies have long been a favorite treat for chocolate lovers, but adding swirls of marshmallow fluff takes them to a whole new level. These marshmallow brownies are rich, ultra-fudgy, and have an irresistibly gooey texture. With deep chocolate flavor, pockets of melted chocolate chips, and fluffy marshmallow swirls, they create a decadent experience that is perfect for any occasion.

This recipe captures the classic flavors of a s’more without the graham crackers. The intense chocolate base provides the richness, while the marshmallow swirls offer a light, airy contrast. The result is a perfectly balanced brownie that combines the best of both worlds—dense, chewy chocolate and soft, gooey marshmallow.

What makes this recipe truly special is its simplicity. You do not need any complicated techniques or hard-to-find ingredients. The batter comes together in just one bowl, and the marshmallow swirl is as easy as dolloping and swirling with a knife. This means you can enjoy homemade bakery-style brownies with minimal effort.

These brownies are perfect for birthday parties, potlucks, or just a weekend baking session. If you love s’mores, hot chocolate, or classic fudgy brownies, you will absolutely love this recipe. Whether you serve them warm with a scoop of vanilla ice cream or enjoy them on their own, these marshmallow brownies are guaranteed to satisfy your sweet tooth.

If you have been searching for the ultimate gooey brownie recipe, look no further. This guide will walk you through everything you need to know to achieve perfect marshmallow brownies every time.

Why You’ll Love This Marshmallow Brownies

There are countless brownie recipes out there, but these marshmallow brownies stand out for several reasons. They combine rich chocolate, gooey marshmallow, and a fudgy texture, making them irresistible. If you love easy, indulgent desserts, here are some reasons why you will love this recipe.

Super Fudgy and Gooey

The best brownies are the ones that are moist, dense, and fudgy, and this recipe delivers just that. The combination of melted butter, oil, and eggs creates an ultra-rich texture, while the marshmallow adds extra gooeyness. These brownies are never dry or cakey, making them perfect for chocolate lovers who enjoy a soft and chewy bite.

Easy to Make in One Bowl

You do not need any fancy equipment or multiple mixing bowls for this recipe. Everything comes together in one bowl, which means less cleanup and less hassle. If you are new to baking, this recipe is simple and foolproof, making it a great starting point for homemade brownies.

The Perfect Balance of Chocolate and Marshmallow

Chocolate and marshmallow are a classic combination. The deep, bittersweet chocolate base contrasts beautifully with the light, fluffy sweetness of marshmallow fluff. Every bite is a perfect balance of rich and sweet flavors.

Great for Any Occasion

These brownies are perfect for holidays, parties, or even casual weeknight desserts. Their eye-catching swirls and irresistible texture make them a great choice for gifting or bringing to events. Plus, they can be easily stored or frozen, so you can always have a delicious treat on hand.

Customizable with Fun Add-Ins

If you love experimenting with flavors, these brownies are a great base for creativity. You can add crushed graham crackers for a full s’mores effect, mix in caramel swirls, or top them with chopped nuts or chocolate chunks. There are endless ways to customize them to your taste.

If you love decadent, gooey, and deeply chocolatey desserts, these marshmallow brownies will quickly become your new favorite recipe.

Health Benefits of Marshmallow Brownies

While brownies are undoubtedly an indulgence, this recipe does contain some surprising benefits when made with high-quality ingredients. By baking from scratch, you have full control over what goes into your dessert, making them a better option than store-bought sweets.

Dark Chocolate Provides Antioxidants

Using Dutch-process cocoa powder and semi-sweet chocolate chips means these brownies contain flavonoids and antioxidants, which may help support heart health and reduce inflammation. Dark chocolate has also been linked to mood-boosting effects due to its ability to stimulate endorphin production.

Marshmallow Fluff is Lighter Than Frosting

While marshmallow fluff adds sweetness, it is lower in fat compared to butter-based frostings. This means you get a sweet, fluffy topping without the heaviness of traditional frosting. If you want to reduce sugar content, you can opt for homemade marshmallow fluff with natural sweeteners.

Less Sugar Compared to Store-Bought Brownies

Many commercial brownie mixes contain preservatives, artificial flavors, and excessive sugar. By making brownies at home, you can control the amount of sugar and use higher-quality ingredients, resulting in a cleaner, more wholesome treat.

Source of Healthy Fats

The combination of butter and oil in this recipe provides a mix of saturated and unsaturated fats, which helps create the moist, fudgy texture. Using a high-quality vegetable oil like avocado oil or coconut oil can also add some healthier fats to the brownies.

Eggs Add Protein and Essential Nutrients

Eggs play a key role in creating the perfect brownie structure, but they also add protein, vitamin D, and B vitamins. These nutrients help support overall energy levels and metabolism.

While these brownies should be enjoyed in moderation, making them from scratch ensures that you are getting the best possible ingredients while still indulging in a delicious homemade treat.

Preparation Time, Servings, and Nutritional Information Marshmallow Brownies

Preparation Time

• Prep Time: 15 minutes
• Baking Time: 45-55 minutes
• Cooling Time: 30 minutes
• Total Time: 1 hour 30 minutes

Servings

This recipe makes 12 large brownies or 16 smaller brownies, depending on how you slice them.

Nutritional Information (Per Brownie, Based on 12 Servings)

• Calories: 320 kcal
• Carbohydrates: 38g
• Protein: 4g
• Fat: 18g
• Sugar: 28g
• Fiber: 2g

The nutritional values may vary based on portion size and ingredient modifications.

Ingredients List Marshmallow Brownies

 Brownies:

• 2 cups granulated sugar
• 3 large eggs + 1 egg yolk
• ½ cup unsalted butter, melted
• 2 teaspoons pure vanilla extract
• ½ cup oil (canola or vegetable)
• ¾ cup all-purpose flour
• 1 cup unsweetened cocoa powder (preferably Dutch-process)
• 1½ tablespoons cornstarch
• ½ teaspoon salt
• 1 cup semi-sweet chocolate chips

 Marshmallow Swirl:

• 1 cup marshmallow crème or fluff

Step-By-Step Cooking Instructions Marshmallow Brownies

 1: Gather Your Ingredients & Tools

Before we start, let’s make sure we have everything ready.

Ingredients You’ll Need:

✅ For the Brownies:

• 2 cups granulated sugar
• 3 large eggs + 1 egg yolk (extra yolk makes them extra fudgy!)
• ½ cup unsalted butter, melted
• 2 teaspoons pure vanilla extract
• ½ cup vegetable or canola oil
• ¾ cup all-purpose flour
• 1 cup unsweetened cocoa powder (Dutch-process preferred for deeper flavor)
• 1½ tablespoons cornstarch (helps create a soft, chewy texture!)
• ½ teaspoon salt
• 1 cup semi-sweet chocolate chips (or chopped chocolate for extra gooeyness!)

✅ For the Marshmallow Swirl:

• 1 cup marshmallow crème or marshmallow fluff

🔥 Pro Tip: Use high-quality chocolate and cocoa powder for the best flavor. The richer the cocoa, the deeper the chocolate taste!

Tools You’ll Need:

9×9-inch baking pan (lined with parchment paper for easy removal)
Mixing bowls
Electric hand mixer or stand mixer
Whisk and spatula
Sifter (for dry ingredients)
Toothpick (for doneness test)

 2: Prep the Baking Pan & Oven

1️⃣ Preheat your oven to 325°F (163°C).
2️⃣ Grease a 9×9-inch baking pan with butter or nonstick spray.
3️⃣ Line the pan with parchment paper, leaving an overhang on the sides—this makes it easier to lift out the brownies later.

🔥 Why This Step Matters: Lining the pan prevents sticking and allows for perfect, clean slices!

 3: Mix the Dry Ingredients

1️⃣ In a medium mixing bowl, sift together:

• ¾ cup all-purpose flour
• 1 cup unsweetened cocoa powder
• 1½ tablespoons cornstarch
• ½ teaspoon salt

2️⃣ Whisk everything together until evenly combined.

🔥 Why Sifting? Sifting the cocoa and flour prevents lumps and creates a smooth, lump-free brownie batter.

 4: Beat the Eggs & Sugar

1️⃣ In a large mixing bowl, combine:

• 2 cups granulated sugar
• 3 eggs + 1 egg yolk

2️⃣ Beat on high speed for 5 minutes using an electric mixer. The mixture should become pale, thick, and fluffy.

🔥 Why This Step? Beating the eggs and sugar incorporates air into the batter, which gives the brownies a slightly crackly top—just like bakery-style brownies!

 5: Add the Wet Ingredients

1️⃣ Reduce the mixer to low speed and add:

• ½ cup melted butter
• ½ cup vegetable oil
• 2 teaspoons vanilla extract

2️⃣ Mix until just combined—don’t overmix!

🔥 Why Use Butter & Oil? Butter adds richness, while oil keeps the brownies super moist and fudgy.

 6: Combine Wet & Dry Ingredients

1️⃣ Slowly add the dry ingredients to the wet mixture.
2️⃣ Use a spatula to fold the batter gently until just combined.
3️⃣ Stir in 1 cup of chocolate chips, distributing them evenly.

🔥 Mixing Tip: Don’t overmix! Overworking the batter can make the brownies too dense instead of fudgy.

 7: Pour Batter & Swirl in Marshmallow Fluff

1️⃣ Pour the brownie batter into the prepared pan, spreading it evenly with a spatula.
2️⃣ Warm the marshmallow fluff slightly in the microwave for 10 seconds (this makes it easier to swirl).
3️⃣ Dollop spoonfuls of marshmallow fluff over the brownie batter.
4️⃣ Use a knife or skewer to swirl the marshmallow into the batter, creating a marbled effect.

🔥 Pro Tip: For a more dramatic swirl, drag a knife through the marshmallow in a zig-zag pattern!

 8: Bake the Brownies

1️⃣ Bake at 325°F (163°C) for 45-55 minutes.
2️⃣ The edges should be set, but the center should still look slightly underbaked.
3️⃣ Insert a toothpick in the center—it should come out with a few moist crumbs, not wet batter.

🔥 Why Slightly Underbaked? Brownies continue to set as they cool, so taking them out when slightly gooey ensures the perfect fudgy texture.

 9: Cool Completely Before Slicing

1️⃣ Let the brownies cool in the pan for at least 1 hour.
2️⃣ For clean cuts, refrigerate for 10 minutes before slicing.

🔥 Cutting Tip: Use a sharp knife, wiped clean after each cut, for perfect, bakery-style slices.

How to Serve Marshmallow Brownies

Best Ways to Serve:

🍦 Warm with Ice Cream – Vanilla or caramel ice cream makes these brownies even more indulgent.
☕ With Coffee or Hot Chocolate – The perfect cozy dessert pairing.
🍓 With Fresh Berries – Strawberries or raspberries add a tart contrast to the rich chocolate.
🍫 Drizzled with Melted Chocolate – Extra chocolate never hurts!

🔥 Pro Tip: For extra gooey brownies, microwave for 10 seconds before serving!

Pairing Suggestions 

Best Drinks to Pair With Brownies:

☕ Espresso or Cappuccino – The bitterness of coffee balances the sweetness.
🥛 Cold Milk – A classic combo that never fails!
🍷 Dark Hot Chocolate – Double the chocolate, double the fun!

Brunch or Party Pairing Ideas:

🥞 With Fluffy Pancakes – A decadent brunch treat!
🍩 With Doughnuts – The ultimate chocolate-lover’s spread.
🍪 With Cookies – Serve alongside chewy chocolate chip cookies for a dessert platter.

Storage, Freezing & Reheating Instructions 

 Store Brownies:

• Store at room temperature in an airtight container for up to 5 days.
• In the fridge, they last up to 7 days (but they firm up).

 Freeze Brownies:

1️⃣ Cut brownies into squares.
2️⃣ Wrap each piece in plastic wrap, then place in a ziplock bag.
3️⃣ Freeze for up to 1 month.

🔥 Thawing Tip: Let frozen brownies sit at room temperature for 1 hour before eating.

 Reheat Brownies:

• Microwave: 10-15 seconds for gooey brownies.
• Oven: Bake at 300°F for 5 minutes for a fresh-baked texture.

Common Mistakes to Avoid

Even though these Marshmallow Brownies are easy to make, a few mistakes can impact their texture, flavor, and overall gooeyness. Avoid these common errors for perfectly fudgy brownies with gorgeous marshmallow swirls!

1. Overmixing the Batter

• Once you add the dry ingredients to the wet mixture, mix just until combined. Overmixing will develop the gluten, leading to dense, tough brownies instead of soft, fudgy ones.

2. Overbaking the Brownies

• Brownies continue to cook as they cool, so remove them from the oven when the edges are set but the center is slightly underbaked.
• A toothpick test should come out with moist crumbs, not completely clean.

3. Not Beating the Eggs and Sugar Long Enough

• The whipped egg-sugar mixture is key to creating that shiny, crackly top.
• Beat them on high speed for at least 5 minutes until the mixture becomes thick and pale. Skipping this step will result in a flat, dull brownie top.

4. Using Cold Ingredients

• Cold eggs or butter can cause the batter to seize up, making it hard to mix.
• Ensure all ingredients are at room temperature for a smooth, even batter.

5. Not Swirling the Marshmallow Properly

• If you mix the marshmallow fluff too much, it will disappear into the batter instead of forming distinct gooey swirls.
• Use a butter knife or toothpick to gently swirl it into the batter without over-incorporating.

By avoiding these mistakes, you’ll get ultra-fudgy brownies with perfect marshmallow ribbons in every bite!

Pro Tips for the Best Marshmallow Brownies

Want next-level brownies that taste like they came from a bakery? Follow these expert tips for rich, gooey, and indulgent results!

1. Use High-Quality Cocoa Powder

• Dutch-process cocoa makes brownies darker, richer, and more chocolatey.
• If using natural cocoa powder, consider adding ½ teaspoon of espresso powder to enhance the chocolate flavor.

2. Melt the Marshmallow Fluff for Easier Swirling

• Microwave the marshmallow fluff for 5-10 seconds before adding it to the batter. This makes it easier to dollop and swirl without clumping.

3. For Extra Fudginess, Use More Egg Yolks

• Egg yolks add richness and moisture.
• If you love ultra-fudgy brownies, replace one whole egg with an extra yolk.

4. Chill Brownies Before Slicing for Clean Edges

• Gooey brownies are tricky to cut, but chilling them in the fridge or freezer for 10-15 minutes makes slicing easier.
• Use a sharp knife cleaned between cuts for neat, bakery-style squares.

5. Add Chocolate Chunks for Pockets of Melted Chocolate

• Folding in chunks of semi-sweet or dark chocolate instead of just chocolate chips creates melty, rich pockets of chocolate throughout the brownies.

6. Pair with the Right Toppings

• Serve warm brownies with:
  • A scoop of vanilla ice cream for a classic pairing.
  • A drizzle of warm chocolate or caramel sauce for extra indulgence.
  • Crushed graham crackers on top for a s’mores-inspired twist.

Following these tips will take your marshmallow brownies from good to absolutely unforgettable!

Frequently Asked Questions (FAQs)

1. Can I Use Regular Marshmallows Instead of Marshmallow Fluff?

• Yes! If using regular marshmallows, cut them into halves or quarters and gently press them into the batter before baking. They will melt into gooey pockets of marshmallow.

2. How Do I Store These Brownies?

• Store in an airtight container at room temperature for up to 5 days.
• If you like them extra fudgy, store them in the fridge and warm slightly before eating.

3. Can I Freeze Marshmallow Brownies?

• Yes! Wrap brownies individually in plastic wrap, then store in a freezer-safe bag for up to 1 month.
• Thaw at room temperature or microwave for 15-20 seconds before serving.

4. How Do I Make These Brownies Extra Gooey?

• Use less flour (reduce by 2 tbsp) for a softer texture.
• Bake 5 minutes less than usual, then let them set before slicing.

5. Why Didn’t My Brownies Get a Crackly Top?

• The key to a crackly top is beating the eggs and sugar until thick and pale before adding the rest of the ingredients.
• Also, don’t overmix once the flour and cocoa powder are added.

6. Can I Use a Boxed Brownie Mix Instead?

• Yes! Simply prepare the mix as directed, then swirl in marshmallow fluff before baking for an easy shortcut.

7. How Do I Prevent My Brownies from Sticking to the Pan?

• Grease your baking pan and line it with parchment paper with an overhang. This makes it easy to lift the brownies out for clean slicing.

8. Can I Add Other Mix-Ins?

• Absolutely! Try these fun variations:
  • Chopped walnuts or pecans for a nutty crunch.
  • Mini chocolate chips for extra chocolate flavor.
  • A sprinkle of sea salt on top for a sweet-salty contrast.

9. What’s the Best Way to Reheat Brownies?

• Microwave for 15-20 seconds for a warm, gooey texture.
• Reheat in the oven at 300°F for 5-7 minutes if you prefer a crispy edge.

10. Can I Make These Gluten-Free?

• Yes! Use a 1:1 gluten-free flour blend instead of all-purpose flour.

These FAQs cover everything you need to know to customize, store, and perfect your marshmallow brownies!

Conclusion & Call to Action

These Marshmallow Brownies are the ultimate gooey, fudgy, and chocolate-packed dessert. With ribbons of marshmallow fluff swirled into rich chocolate batter, they’re an irresistible treat for any occasion! Whether you’re making them for a party, a cozy night in, or just because—you won’t regret it.

Why You’ll Love This Recipe

Super fudgy texture with a shiny crackly top.
Swirls of gooey marshmallow for extra indulgence.
Easy to customize – Add nuts, caramel, or extra chocolate chips.
Perfect for freezing & meal prep – Enjoy brownies anytime!

Now it’s your turn to bake!

👉 Try these Marshmallow Brownies and let me know how they turn out! Did you use marshmallow fluff or regular marshmallows? Did you add any fun mix-ins? Drop a comment below!

📸 Snap a pic and tag me on Instagram – I’d love to see your brownie creations!

Happy baking! 🍫🔥✨

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