Marshmallow Brownies Easy Recipes With Marshmallows And Brownie Toppings

Posted on October 29, 2025

Craving something rich, gooey, and satisfyingly sweet? Marshmallow brownies are the ultimate comfort dessert—especially when combined with the nutty depth of peanut butter and the crispy crunch of rice cereal toppings. This easy recipe transforms a basic brownie mix into a show-stopping layered treat loaded with mini marshmallows, chopped Reese’s peanut butter cups, and a silky chocolate-peanut butter topping.

Whether you’re planning a weekend bake or looking for something indulgent to serve at your next gathering, this recipe balances simplicity with bakery-style flavor. It uses everyday pantry ingredients but creates a multi-textured bite with each layer—from the fudgy base to the gooey marshmallows and crispy topping. For anyone looking for easy brownie recipes, this one is beginner-friendly and delivers professional results.

What makes this treat even more irresistible is its nostalgic combination of flavors—like a mix between a s’mores dessert and a candy bar. Learn how to prepare these peanut butter marshmallow brownies in just a few steps, with expert tips to ensure the perfect bake every time. You can even tweak the ingredients to suit your preference: swap peanut butter with Nutella, use chopped nuts, or add a drizzle of caramel. For those who love baking creative bake sale treats or need a dessert for a holiday dessert tray, this one delivers both taste and visual appeal.

Discover how ingredients like marshmallows, Reese’s Peanut Butter Cups, and Rice Krispies come together in this easy yet elevated dessert. For a deeper dive into the history of these components, check out resources like the Wikipedia entry on marshmallows and learn about Rice Krispies, a cereal that adds the perfect crunch to your topping layer.

Why You’ll Love These Marshmallow Brownies

If you’re someone who enjoys fudgy brownies but craves more texture, contrast, and fun in your desserts, these peanut butter marshmallow brownies are for you. They’re not just another bar treat—they’re a multi-layered experience of gooey, crispy, melty, and chewy textures that make every bite memorable.

Quick and Easy: The base uses a boxed brownie mix, which saves time while still delivering a rich, chocolatey foundation. If you’re in a pinch, this is the ultimate shortcut for easy peanut butter brownies that taste homemade.
Layers of Flavor: Between the chopped Reese’s Peanut Butter Cups, puffed mini marshmallows, and the chocolate-peanut butter cereal topping, there’s no shortage of delicious contrasts in every bite.

Family Favorite: These brownies are loved by kids and adults alike. Whether you’re prepping for a family movie night or whipping up treats for a school bake sale, they’ll disappear fast.
Perfect for Events: Planning to make a holiday dessert tray or need a standout bake sale treat? These brownies look as good as they taste. You can dress them up with drizzled chocolate, colored sprinkles, or even a dash of sea salt.
Customizable: Don’t have Reese’s? Use peanut butter chips or other candies. Want more crunch? Add crushed graham crackers or chopped nuts. You can even take flavor inspiration from Pinterest’s best s’mores desserts and modify the toppings accordingly.

For more brownie variations, the Wikipedia page on brownies offers insight into how this humble dessert evolved into a beloved classic. It’s easy to see why it continues to be one of the most adaptable and crowd-pleasing sweets in modern baking. With just a few ingredients and some creativity, you can reinvent the classic brownie into something unforgettable.

Ingredients Breakdown and Substitutions

Creating the perfect peanut butter marshmallow brownie starts with understanding how each ingredient plays a role. From texture to flavor balance, these components come together to create a dessert that’s gooey, crisp, and indulgent. Here’s a breakdown of what you’ll need—and how you can adapt it to suit your pantry or preferences.

Boxed Brownie Mix:
The foundation of this recipe, a boxed brownie mix, offers consistency and speed. Look for a fudgy version for the richest results. Brands like Ghirardelli or Betty Crocker are widely trusted. If you prefer homemade, use your go-to brownie base—just make sure it fits a 9×13 pan. You can explore brownie variations on Pinterest for more ideas.
Mini Marshmallows:
These create a gooey, sticky layer that contrasts with the dense brownie base and crunchy topping. If you don’t have mini marshmallows, you can cut large ones into smaller pieces or swirl in marshmallow fluff. Just be mindful that fluff melts faster and spreads more.

Reese’s Peanut Butter Cups:
The chopped candy provides a rich peanut butter-chocolate combo. You can substitute:
- Peanut butter chips for a similar flavor with less sweetness.
- M&Ms, Snickers, or chopped chocolate bars for a custom twist.
  Learn more about Reese’s Peanut Butter Cups if you’re curious about how this candy became such a baking staple.

Milk Chocolate Chips & Creamy Peanut Butter (for topping):
When melted together, these create a thick, spreadable ganache. Use high-quality chips and smooth peanut butter for best texture. Avoid natural peanut butter with oil separation unless well-stirred.
Crispy Rice Cereal:
This cereal adds the essential crunch to the topping layer. Its lightness balances the richness of the brownie and peanut butter. Not limited to Rice Krispies—you can use store brands or crushed cornflakes for a different crunch profile. Rice Krispies cereal has long been a favorite for adding texture to no-bake and layered desserts.

Optional Add-Ins and Swaps

Sea salt flakes for a salty-sweet contrast.

Chopped walnuts or pecans for nutty depth.
Crushed graham crackers to give a s’mores effect.
Caramel drizzle for added decadence.

Add chocolate chunks to the brownie mix for extra richness.

For visual inspiration on how to customize or decorate your brownies, check out creative peanut butter chocolate bar ideas on Pinterest. These little changes can turn a great brownie into your personal signature dessert.

Tools You’ll Need

Making these marshmallow peanut butter brownies is straightforward, but having the right tools ensures the best results and makes cleanup easier. Here’s a checklist of kitchen essentials that will help you achieve perfectly baked, layered brownies with clean, professional-looking cuts.

9×13-Inch Baking Pan:
This is the ideal size for the recipe. It gives the brownies enough room to rise while keeping the layers proportional. Using a metal pan is recommended for even heat distribution. If you’re using glass or ceramic, you may need to adjust the baking time slightly.

Parchment Paper (Optional but Recommended):
Lining your pan with parchment allows for easy removal and cutting. It also prevents sticking, especially with the marshmallow layer. For tips on preparing desserts for events, explore holiday dessert tray ideas.
Mixing Bowls (2-3):
You’ll need at least one large bowl for the brownie batter and another for melting the chocolate chips and peanut butter. A third small bowl can be handy for prepping chopped candies or cereal.
Microwave-Safe Bowl or Double Boiler:
For melting the chocolate and peanut butter mixture. Microwave in 30-second intervals or use a double boiler to prevent scorching.

Spatula:
A rubber spatula helps evenly spread both the brownie batter and the crispy topping layer without tearing the puffed marshmallows underneath.
Sharp Knife or Bench Scraper:
Once cooled, a sharp knife (preferably warmed under hot water and wiped dry) will give you cleaner cuts through the dense layers. A bench scraper also works well if you’re cutting into uniform bars for events like a bake sale.
Toothpick or Cake Tester:
Use this to check if the brownies are done before adding toppings. The center should come out mostly clean—some moist crumbs are okay for that fudgy texture.

These basic tools help streamline the process and contribute to the final appearance and texture of the dessert. If you’re frequently baking peanut butter desserts, it’s worth investing in quality bakeware for consistent results. You can also explore curated bake sale treat ideas to see how presentation tools can enhance your final product.

Step-by-Step Recipe Instructions (Part 1)

Creating these peanut butter marshmallow brownies is simple when broken down into steps. Each layer builds on the last to create a multi-textured, indulgent dessert. Follow the instructions below carefully for the best results.

Step 1: Preheat and Prepare

Preheat your oven according to the directions on the brownie mix box—usually 325°F to 350°F depending on the brand. Grease a 9×13-inch baking pan with non-stick spray or line it with parchment paper for easy removal.

Step 2: Mix the Brownie Batter

In a large mixing bowl, prepare the brownie batter according to the box instructions, usually combining oil, eggs, and water. Stir just until the batter is smooth—avoid overmixing, as this can lead to cakier brownies instead of a fudgy texture.

Step 3: Bake the Brownies

Pour the batter evenly into the prepared pan. Tap the pan gently on the counter to remove air bubbles and level the top. Bake according to the time listed on the box for a 9×13 pan—generally 22–28 minutes. Start checking at the minimum time mark. Insert a toothpick into the center; it should come out with a few moist crumbs, not wet batter.

Step 4: Add Marshmallows

Immediately after removing the brownies from the oven, sprinkle 1 cup of mini marshmallows evenly over the top. The heat from the brownies will start to soften them.

Return the pan to the oven for 2–3 minutes only, just until the marshmallows puff and begin to melt slightly. Do not overbake or they’ll melt too much and lose their structure.

Step-by-Step Recipe Instructions (Part 2)

Step 5: Add the Reese’s

Once the marshmallows are puffed, remove the pan from the oven and sprinkle 1 cup of chopped Reese’s Peanut Butter Cups across the top. Press them gently into the marshmallow layer so they stick as it cools.

Step 6: Prepare the Topping

In a microwave-safe bowl, combine 1 cup of milk chocolate chips and ½ cup of creamy peanut butter. Heat in 30-second intervals, stirring between each, until the mixture is fully melted and smooth. This should take about 1–1½ minutes total.

Step 7: Mix in the Crispy Cereal

Stir 1½ cups of crispy rice cereal into the melted chocolate-peanut butter mixture until the cereal is fully coated. This layer adds a satisfying crunch that contrasts beautifully with the gooey base.

Step 8: Spread the Topping

Gently spread the cereal mixture over the top of the brownies. Do this carefully so you don’t disturb the marshmallow or candy layers beneath. Use a spatula or the back of a spoon to press it into an even layer.

Step 9: Cool and Cut

Allow the brownies to cool completely at room temperature—this may take 1–2 hours. For cleaner cuts, you can chill them in the refrigerator for 30–60 minutes after cooling. Use a sharp knife warmed under hot water (and wiped dry) to slice into squares.

Store leftovers in an airtight container at room temperature for up to 3 days, or refrigerate for up to a week.

Pro Tips for the Best Marshmallow Brownies

Use parchment paper to lift the brownies out of the pan easily—especially helpful for clean slicing.
Slightly underbake the brownie base for a fudgier center. This keeps the texture soft and gooey without being raw.

Cool completely before cutting to prevent the toppings from pulling apart or smearing.
Use smooth, commercial peanut butter for consistent melting. Natural peanut butter with oil separation can lead to uneven texture.
Don’t skip the crispy rice cereal topping—it gives the brownies their signature layered crunch.

If you’re a fan of s’mores desserts, this treat gives you similar flavors in a handheld form. You can find variations and creative decorating ideas on Pinterest, including using white chocolate, butterscotch chips, or even a graham cracker crumble.

Topping Variations & Customizations

These brownies are extremely versatile. Here are some fun and flavorful ways to switch up the toppings:

Nutella instead of peanut butter: Swap the peanut butter for Nutella in the topping mixture for a hazelnut twist.
S’mores-style topping: Add crushed graham crackers and a chocolate drizzle for a campfire feel.

Salty-sweet combo: Sprinkle with flaky sea salt after spreading the topping to enhance all the flavors.
Add crushed pretzels or potato chips: These bring a salty crunch and unique texture.
Oreo or M&M topping: Press in crushed Oreo cookies or colorful M&Ms for a fun party vibe.

Browse Pinterest’s peanut butter chocolate bar ideas to see how others customize their bars with toppings and mix-ins for different occasions.

Storage & Make-Ahead Instructions

Room Temperature: Store cut brownies in an airtight container at room temp for up to 3 days. Keep layers from sticking by placing parchment between them.

Refrigeration: Store up to 1 week in the fridge. Let them sit at room temperature for 10–15 minutes before serving for the best texture.
Freezing: Wrap individual squares in plastic wrap, then store in a zip-top freezer bag. Freeze for up to 2 months. Thaw at room temperature or microwave for 10 seconds before eating.

This makes them a great candidate for prepping ahead for parties, school lunches, or gifting. You’ll also find these types of treats are ideal for building holiday dessert trays—see examples on Pinterest.

Serving Suggestions

Serve these marshmallow brownies as-is or elevate them with creative pairings:

Top with a scoop of vanilla ice cream for a brownie sundae.
Drizzle with melted chocolate or caramel for extra richness.
Pair with hot cocoa for a cozy winter dessert.

Cut into smaller pieces and add to a bake sale or party platter.

Need inspiration for how to present them at your next event? Check out visual bake sale treats ideas on Pinterest.

Common Mistakes to Avoid

Overbaking the brownies: This dries them out. Use the toothpick test and aim for moist crumbs, not a clean stick.
Adding marshmallows too early or too late: They’ll either dissolve or fail to melt. Add them right after baking and return to the oven for 2–3 minutes only.
Not cooling before topping: Topping too soon or while the marshmallow layer is unstable can cause mixing or collapse.

Using the wrong peanut butter: Natural peanut butter can separate. Use a no-stir variety for a smooth, stable topping.
Cutting brownies while warm: This leads to messy cuts and pulls apart the toppings. Always cool fully or chill before slicing.

Avoiding these simple errors ensures you end up with beautiful, delicious bars every time.

FAQs

Can I make these brownies without peanut butter?
Yes. Swap the peanut butter for Nutella, almond butter, or simply use all melted chocolate for the topping.

Can I use a homemade brownie mix instead of a boxed one?
Absolutely. Just make sure it yields enough batter for a 9×13 pan and has a dense, fudgy consistency.

Can I make these gluten-free?
Yes. Use a gluten-free brownie mix and double-check that all other ingredients (like cereal and candy) are certified gluten-free.

How do I make them more gooey or fudgy?
Slightly underbake the brownie base, and avoid overmixing the batter. Use a moist boxed mix or add an extra egg yolk for richness.

How do I keep the marshmallows from burning?
Only return the pan to the oven for 2–3 minutes after adding the marshmallows. Watch closely and remove as soon as they puff.