Peanut Butter Cup Brownies feature a gooey brownie base studded with peanut butter cups and finished with a rich peanut butter-and-chocolate topping — a show-stopping dessert for any occasion.
author’s note
Peanut Butter + Chocolate = The Best Brownies Ever!
Each Halloween we save extra Reese’s from the kids’ candy and turn them into these brownies — it’s a family tradition now. When time is tight I’ll use a boxed mix, but for the fudgiest base we often bake from scratch.
Peanut Butter Cup Brownies Ingredients
| Ingredient | Notes / Substitutions |
|---|---|
| Brownie mix (9 × 13 in. size) | Any brand works. You can also use a homemade brownie recipe as long as it fits a 9×13 pan. |
| Eggs, oil, water | Follow the mix directions. Swap melted butter or cooled coffee for depth of flavor. |
| Original-sized Reese’s peanut butter cups | Large cups create generous peanut butter pockets; mini cups work too. |
| Milk chocolate chips | Use semi-sweet or dark chocolate to reduce sweetness if preferred. |
| Creamy sweetened peanut butter (not natural) | Natural peanut butter can separate; creamy, stabilized peanut butter gives a smooth topping. |
| Coconut oil or shortening (divided) | Helps the chocolate and peanut butter melt smoothly; butter can be used in a pinch. |
Fun Variations
- Bake in muffin tins for individual brownie “cups.”
- Swirl 1/4 cup peanut butter into the batter for peanut butter ribbons throughout.
- Sprinkle flaky sea salt over the warm topping for contrast.
- Fold chopped salted peanuts into the topping for added crunch.
How To Make Peanut Butter Cup Brownies
- Prep the pan: Line a 9 × 13-inch pan with parchment and preheat the oven according to the brownie mix instructions.
- Mix and bake: Prepare the batter per package directions and bake for about two minutes less than recommended so the center stays slightly underbaked and gooey.
- Add the cups: Quickly unwrap and press the peanut butter cups evenly into the soft brownie surface (three rows of five works well). Return to the oven for the remaining two minutes.
- Top it: Let the brownies cool completely. Melt the chocolate chips with 2 tablespoons of coconut oil or shortening in short bursts, stirring until smooth. Spread over the cooled brownies. In a separate bowl melt 3/4 cup creamy peanut butter with the remaining 1/2 tablespoon oil, stir in optional vanilla, and drizzle across the chocolate. Marble gently with a knife, only through the top layers.
- Set and slice: Allow the topping to firm at room temperature (do not chill). For clean slices, use a sharp knife warmed under hot water, dried, and wiped between cuts. Remove bars with a metal spatula.
Tips For Success
- Use room-temperature eggs to help create a shiny brownie crust.
- Melt chocolate in 20-second microwave bursts, stirring thoroughly between each burst to prevent burning.
- No peanut butter cups? Press peanut butter chips into the half-baked brownies and add a warm drizzle of peanut butter for a similar effect.
Quick Tip
Spotty or streaky chocolate is caused by cocoa solids separating and is safe to eat. It may appear if the brownie base is cold when you pour the topping or if the topping is chilled after setting.
Storage
Peanut Butter Cup Brownie Storage
Room temperature: Cover tightly and enjoy within 3–5 days for best texture and flavor.
Freezer: Wrap individual squares in parchment and place in a zip bag; freeze up to two months. Thaw at room temperature. White “bloom” on chocolate after thawing is harmless.
More Chocolate-Peanut Butter Recipes:
Desserts
No Bake Peanut Butter Cheesecake
Desserts
Peanut Butter Brownie Bites
Peanut Butter Cup Brownies
Equipment
- 9 x 13-inch baking pan
- Parchment paper
Ingredients
- 1 (18.3-ounce) package fudge brownie mix plus ingredients called for on the mix
- 15 regular-sized Reese’s peanut butter cups, unwrapped
- 2-1/2 cups milk chocolate chips
- 3/4 cup creamy peanut butter
- 1 teaspoon vanilla extract (optional)
- 2-1/2 tablespoons shortening or coconut oil, divided
Instructions
- Line a 9×13-inch pan with parchment paper and preheat the oven per the brownie mix directions.
- Prepare the brownies according to the package. Pour into the prepared pan and bake for 2 minutes less than the package directs. Unwrap the peanut butter cups while baking.
- Press the unwrapped peanut butter cups into the soft brownie surface in an even grid (three rows of five).
- Return the pan to the oven for the remaining 2 minutes. Remove and cool completely to room temperature. If chilled, allow to come back to room temperature before topping.
- Combine chocolate chips and 2 tablespoons shortening or coconut oil in a microwave-safe bowl. Microwave in 20-second bursts, stirring between bursts until melted and smooth. Spread over cooled brownies.
- In another bowl combine peanut butter and remaining 1/2 tablespoon oil. Microwave about 30 seconds and stir until smooth. Stir in vanilla if using. Drizzle peanut butter over the chocolate and marble gently with a knife without cutting into the brownies.
- Allow brownies to set at room temperature (do not chill). For clean slices, heat a sharp knife under hot water, dry it, then cut. Repeat between cuts and lift squares with a metal spatula.
Recipe Notes
Note 1: Choose a brownie mix known to bake well in a 9×13-inch pan. Homemade brownies work too.
Note 2: If the brownie base is cold when you add the chocolate topping, it can develop streaks or bloom; this is purely cosmetic and safe to eat. Chilling after topping can make cutting messy, so room temperature is best.
Note 3: Chocolate continues to melt after microwaving; use short bursts and stir thoroughly to avoid overheating.
Storage: Store covered at room temperature for 3–5 days. Freeze wrapped squares for up to two months; thaw at room temperature.
Nutrition
Calories: 208 kcal |
Carbohydrates: 24 g |
Protein: 4 g |
Fat: 11 g
Nutrition values are approximate and do not include the brownie mix’s own nutrition, which varies by brand.