Name: Reese's Peanut Butter Swirl Brownies Recipe
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Cuisine: American
Ingredients: 1 cup butter, melted; 2 cups sugar; 3/4 cup cocoa powder; 2 tsp vanilla extract; 4 eggs; 1 1/2 cups all-purpose flour; 1/2 tsp salt; 3/4 cup creamy peanut butter; 3/4 cup miniature Reese's peanut butter cups, chopped; 2 cups miniature Reese's peanut butter cups, chopped

Jump to Recipe· 3.9 from 11 reviews

I absolutely adore this Reese's Peanut Butter Swirl Brownies Recipe because it brings together two of my all-time favorite flavors: rich, fudgy chocolate and creamy, irresistible peanut butter. Every time I make these brownies, I get excited about the luscious swirls of peanut butter mingling with the dense chocolate, creating a dessert that's both comforting and delightfully indulgent. Plus, the chopped miniature Reese's peanut butter cups add little pockets of chewy, chocolatey goodness that make each bite an exciting surprise. If you love brownies and peanut butter like I do, this recipe is an absolute must-try!

Why You'll Love This Reese's Peanut Butter Swirl Brownies Recipe

What makes this recipe truly special to me is the heavenly flavor combination. The deep cocoa richness balances perfectly with the sweetness and nuttiness of the peanut butter. I love how the peanut butter isn't just mixed in; it’s swirled on top and baked into the batter, so every bite feels like a perfect harmony of textures and tastes. Then, the chopped Reese’s cups both inside and on top add fun bursts of peanut butter-chocolate magic, making these brownies stand out from your average chocolate dessert.

Another reason I recommend this recipe is how simple and straightforward it is to prepare. I don't consider myself a pastry chef, but even on a busy weekday, I can pull these brownies together quickly with common ingredients. There’s no fancy equipment or complicated techniques—just melt, mix, swirl, and bake. These brownies are also incredibly versatile for any occasion, whether you're hosting a family gathering, bringing a treat to a potluck, or just craving a rich dessert to enjoy alongside your afternoon coffee or tea.

Ingredients You'll Need

The ingredients for this Reese's Peanut Butter Swirl Brownies Recipe are delightfully simple but essential. Each element plays a key role—from the butter that adds moisture, to the cocoa powder that gives the deep chocolate flavor, and the peanut butter that provides that creamy swirl contrast. The chopped miniature Reese’s peanut butter cups are the secret weapon that brings texture and bursts of extra peanut butter-chocolate delight.

Tip!

You’ll find all ingredient quantities in the recipe card below.

Butter: Use melted unsalted butter for richness and moisture in the brownies.
Sugar: Granulated sugar helps create that classic fudgy texture.
Cocoa powder: Unsweetened cocoa powder adds the essential chocolatey depth.
Vanilla extract: A splash of vanilla enhances all the flavors beautifully.
Eggs: Four eggs bind everything and contribute to the dense, cakey texture.
Flour: All-purpose flour provides structure without making the brownies heavy.
Salt: Just a pinch to balance the sweetness and intensify the chocolate.
Creamy peanut butter: The star component that creates the luscious swirl.
Miniature Reese’s peanut butter cups: Chopped for surprise bursts of peanut butter and chocolate.

Directions

Step 1: Chop the miniature Reese's peanut butter cups into small pieces and place them in the freezer to keep them firm while you prepare the batter. Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking pan thoroughly to prevent sticking.

Step 2: In a large bowl, whisk together the melted butter, sugar, and cocoa powder until fully combined and glossy. Then add the eggs one at a time along with the vanilla extract, whisking until the mixture is smooth and silky.

Step 3: Stir in the flour and salt just until combined—overmixing will make the brownies tough. Gently fold in about three-quarters of the chopped peanut butter cups to distribute them evenly through the batter.

Step 4: Spread the brownie batter evenly into the prepared pan. Using a spoon, drop dollops of creamy peanut butter on top of the batter, then swirl it gently with a butter knife to create beautiful marbled patterns that peek through the chocolate.

Step 5: Bake the brownies at 350°F for around 20 minutes. After that, sprinkle the remaining chopped Reese’s peanut butter cups evenly over the surface.

Step 6: Return the brownies to the oven and bake for another 18 to 20 minutes, or until a toothpick inserted near the center comes out with a few moist crumbs but not wet batter. Let the brownies cool completely in the pan before cutting into squares to get those perfect fudgy edges.

Servings and Timing

This Reese's Peanut Butter Swirl Brownies Recipe makes about 20 generous servings, perfect for sharing at parties or family gatherings. Prep time is roughly 15 minutes since the steps are straightforward and quick. The baking time totals around 40 minutes, split between two halves of the process to integrate the topping perfectly. Including cooling time, allow at least 1 hour from start to finish to ensure the brownies set beautifully for clean slicing and the best texture.

How to Serve This Reese's Peanut Butter Swirl Brownies Recipe

When I serve these brownies, I love presenting them on a simple platter so the gorgeous peanut butter swirls and chopped Reese’s pieces are the star of the show. For special occasions, I sometimes dust them lightly with powdered sugar or add a few whole Reese's peanut butter cups on the side for extra flair. These brownies are perfect at room temperature but also delicious slightly warmed, especially if you want the peanut butter to be extra gooey and the chocolate soft.

To really elevate the experience, I often pair them with a cold glass of milk or a cup of rich coffee—both complement the chocolate and peanut butter flavors perfectly. For an adult twist, these brownies are wonderful alongside a glass of port or a peanut butter-flavored cocktail. They shine at informal parties, neighborhood potlucks, holiday celebrations, or whenever you’re craving a crowd-pleasing treat.

I usually cut these into fairly small squares because the richness means a little goes a long way, but depending on your occasion, you could easily go bigger for a more indulgent dessert portion. They’re great as a sweet bite after dinner, a decadent afternoon pick-me-up, or even wrapped as homemade gifts paired with festive packaging.

Variations

I love experimenting with this Reese's Peanut Butter Swirl Brownies Recipe to make it my own or adapt to different dietary needs. For example, swapping the creamy peanut butter with natural or chunky peanut butter adds a more rustic texture and stronger nutty flavor. You can also try using almond butter or sunflower seed butter if you want a different nutty dimension or need to avoid peanuts.

If you’re gluten-free, I recommend substituting the all-purpose flour with a gluten-free baking flour blend—just be sure your blend has xanthan gum or a similar binding agent to keep the texture right. For a vegan twist, you can replace the eggs with flax eggs and use vegan butter; results are slightly different but still delicious and fudgy.

Another variation I adore is mixing in some dark or milk chocolate chunks instead of, or in addition to, the miniature peanut butter cups for more chocolate hits. You could also swirl in a few tablespoons of caramel or chocolate hazelnut spread along with the peanut butter to amp up the decadence. And of course, baking this recipe in muffin tins makes perfect portable brownie bites for snack time!

Storage and Reheating

Storing Leftovers

Once your brownies have cooled completely, I store any leftovers in an airtight container at room temperature if I plan to eat them within 2-3 days. This keeps them chewy and moist without drying out. If your kitchen is warm, or you want to keep them a little longer, storing them in the refrigerator is fine—just bring them back to room temperature before enjoying so the texture is spot on.

Freezing

This recipe freezes beautifully. I usually cut the brownies into individual squares, wrap each piece tightly in plastic wrap, then place them all in a freezer-safe zip-top bag or container. They keep well for up to 3 months frozen. When you want to enjoy one, thaw it overnight in the fridge or on the kitchen counter for a few hours, and it will be almost as fresh as the day you made it.

Reheating

To reheat, I prefer a quick zap in the microwave for about 15-20 seconds if I’m eating one or two pieces. This softens the peanut butter and chocolate, restoring that fresh-baked gooeyness. For larger amounts, you can warm the brownies in a low oven (around 300°F) for 5-10 minutes, covered loosely to avoid drying. Avoid overheating or reheating for too long, as it can dry out the brownies and make the peanut butter less creamy.

FAQs

Can I use natural peanut butter instead of creamy peanut butter?

Absolutely! Natural peanut butter will work fine, though it tends to be a bit less sweet and more oily. You might notice a slightly grainier texture and stronger peanut flavor, which can be quite nice if you prefer less sweetness.

Do I need to chill the peanut butter cups before adding them?

Yes, freezing or chilling the chopped peanut butter cups helps them hold their shape during mixing and baking, preventing them from melting completely and turning the batter greasy.

Can I make this recipe nut-free?

Since peanut butter and Reese’s cups are central to the recipe, making a true nut-free version requires substitutions. You could try using sunflower seed butter and nut-free chocolate cups, but the flavor will be quite different. Otherwise, I’d recommend choosing a different brownie recipe if nut allergies are a concern.

What is the best way to get clean brownie slices?

Allow the brownies to cool fully before cutting, and use a sharp, clean knife. For easier slicing, warm the knife under hot water, dry it, then slice. Wiping the knife clean between cuts also helps keep clean edges.

Can I double this recipe for a larger batch?

Yes! Just use a larger baking dish or two 9x13 pans and adjust the baking time slightly. The brownies will take a little longer to bake if you spread them thicker, so keep an eye on them and use the toothpick test to check doneness.

Conclusion

I truly hope you give this Reese's Peanut Butter Swirl Brownies Recipe a try because it brings so much joy and comfort to any dessert table. It’s one of those recipes that delivers incredible flavor with surprisingly simple steps, making it a favorite in my kitchen and, I’m sure, will soon be in yours. Baking these brownies always feels like a little celebration, and sharing them makes it even better. Happy baking!