Reese’s Peanut Butter Cup Brownies | A Perfect Everyday Indulgence

Can a brownie turn your whole day around?

Yes—especially when it’s packed with full-size Reese’s, smothered in whipped peanut butter frosting, and made with a no-fuss boxed mix. These Reese’s Peanut Butter Cup Brownies take dessert to the next level without making your kitchen a disaster zone.

They’re easy enough to whip up for a casual weekday treat, but indulgent enough to bring to a birthday party or bake sale. With a gooey center, soft crumb, and rich peanut butter-chocolate combo, these brownies are everything you love in a dessert—and more.

Overview

Start with your favorite brownie mix, layer in 15 full-size Reese’s Cups, and top it all off with a fluffy, creamy peanut butter frosting. These bake in a 9×13-inch pan, serve a crowd, and require minimal effort. Customize them with a drizzle, chopped candy, or a scoop of vanilla ice cream.

Total time: 50 minutes
Hands-on time: 20 minutes
Skill level: Easy
Servings: 16

Essential Ingredients

For the Brownies

• 1 (18 oz) box brownie mix
• Ingredients called for on the box (typically eggs, water, oil)
• 15 full-size Reese’s Peanut Butter Cups

For the Frosting

• 3/4 cup creamy peanut butter
• 1/2 cup unsalted butter, room temperature
• 2 1/4 cups confectioners’ sugar
• 4 tablespoons heavy cream
• 1 1/2 teaspoons vanilla extract

Why These Brownies Work

• Reese’s Cups inside offer surprise gooey centers with peanut butter flavor
• Whipped frosting adds a fluffy, creamy contrast to dense brownies
• Box mix base means they’re nearly failproof and easy to prep fast

Tip: Use parchment paper to lift brownies easily from the pan for cleaner slices and effortless frosting.

Step-by-Step Instructions

1. Prepare the pan and batter

Preheat oven to 350°F. Line a 9×13-inch baking dish with parchment paper and lightly grease it.

Prepare the brownie batter as directed on the box. Use the amounts of oil, water, and eggs listed for a 9×13-inch pan.

Spread about two-thirds of the brownie batter into the bottom of the prepared dish and smooth it out.

2. Layer in the Reese’s Cups

Unwrap 15 full-size Reese’s and arrange them in three rows of five across the batter. Gently press them into the surface.

Spoon the remaining brownie batter over the top, covering all the candy completely. Smooth with a spatula.

3. Bake to perfection

Bake for 25–30 minutes or until a toothpick inserted into the center comes out with a few moist crumbs. If you hit a peanut butter cup, test elsewhere to avoid a false read.

Let brownies cool completely in the pan on a wire rack before frosting.

4. Make the peanut butter frosting

In a large bowl, beat the peanut butter and softened butter on medium speed until smooth and creamy.

Gradually add in the confectioners’ sugar, beating slowly to incorporate. Scrape the sides of the bowl as needed.

Pour in the heavy cream and vanilla, then whip on medium-high speed for 2 minutes until light and fluffy.

5. Frost and garnish

Use parchment paper to lift the cooled brownie slab out of the pan. Spread frosting evenly over the surface with an offset spatula.

Optional: Add chopped Reese’s, crushed peanuts, chocolate shavings, or a drizzle of melted chocolate.

Slice into 16 bars and serve. Store leftovers in an airtight container.

Presentation Tips

• Garnish with chopped mini Reese’s for extra texture and visual appeal
• Drizzle with melted chocolate or peanut butter using a piping bag or spoon
• Serve each brownie on a plate with a scoop of vanilla ice cream and chocolate sauce

Storage & Make-Ahead Tips

• Room temp: Store in an airtight container for up to 2 days
• Fridge: Keeps well for up to 5 days; bring to room temperature before serving
• Freezer: Wrap unfrosted brownies tightly in plastic and freeze for up to 2 months. Add frosting after thawing
• Make-ahead: Bake the brownie layer the day before and frost just before serving for best texture

Flavor Variations

• Chocolate Fudge Layer: Add a thin layer of chocolate ganache under the peanut butter frosting
• Crunchy Version: Use crunchy peanut butter and sprinkle crushed pretzels on top
• Nut-Free Version: Sub in Oreo cookies for Reese’s Cups and use sunflower butter in the frosting
• Salted Caramel Peanut Butter: Drizzle with caramel sauce and a pinch of flaky sea salt

Kid-Friendly Tips

• Let kids press the Reese’s Cups into the batter as a fun step
• Use mini muffin tins to make individual Reese’s brownie bites
• Top each piece with candy eyes, sprinkles, or themed toppers for birthdays or holidays

Allergy Swaps

• Dairy-Free: Use dairy-free brownie mix, margarine or vegan butter, and dairy-free milk instead of cream
• Nut-Free: Substitute with cookie chunks (like Biscoff) or marshmallows, and use a nut-free frosting
• Gluten-Free: Use a gluten-free brownie mix and verify all ingredients are certified gluten-free

Troubleshooting Guide

Issue	Cause	Fix
Reese’s cups float to top	Batter too thin or not fully covered	Make sure cups are pressed into batter and covered well
Brownies too dry	Overbaked or oven too hot	Check at 25 minutes and use an oven thermometer
Frosting too thick	Not enough cream or too much sugar	Add 1 Tbsp more cream at a time until spreadable
Frosting too soft	Overmixed or warm kitchen	Chill frosting before using and re-whip briefly

Nutrition (Per Brownie)

Calories: 420
Fat: 26g
Carbs: 42g
Sugar: 31g
Protein: 5g

Conclusion

Reese’s Peanut Butter Cup Brownies are the everyday treat that feels like a guilty pleasure but comes together in minutes. With their gooey chocolate layers, surprise candy centers, and fluffy frosting, they hit every note of indulgence.

Make a batch on a lazy Sunday, bring them to a friend’s potluck, or bake them just because. These brownies don’t need a holiday—they make every day a little sweeter.

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FAQs

Can I use homemade brownie batter instead of box mix?
Absolutely! Use your favorite homemade recipe for a custom twist.

Do I have to frost them?
Nope! They’re delicious plain or with just a drizzle of chocolate.

Can I make these in a different size pan?
Yes. For thicker brownies, use a 9×9-inch pan and extend baking time by 5–8 minutes.

Are these freezer-friendly?
Yes—just freeze unfrosted brownies and add the frosting fresh after thawing.

Can I use mini Reese’s?
You can! Just use enough to cover the surface in a single layer and reduce baking time slightly.