Oven Baked 5-Ingredient Peanut Butter Cup Brownie Bars: The Easiest Decadent Dessert You’ll Make on Repeat

If you love the irresistible combination of rich chocolate brownies and creamy peanut butter cups but want a dessert that comes together with almost no effort, these Oven Baked 5-Ingredient Peanut Butter Cup Brownie Bars are exactly what you need. Fudgy brownie layers studded with peanut butter cups and topped with a smooth chocolate finish—this is the kind of simple baking trick a practical home cook keeps in her apron pocket for potlucks, bake sales, and holiday gatherings.

Whether you’re making a treat for a church supper, a family celebration, or simply a sweet craving on an ordinary day, this easy peanut butter cup brownie bar recipe checks every box. It’s budget-friendly, uses just five everyday ingredients, and delivers a dessert that tastes like you spent hours in the kitchen.

Why You’ll Love This 5-Ingredient Peanut Butter Cup Brownie Bars Recipe

The beauty of this recipe is its simplicity. You don’t need a long list of ingredients or fancy equipment—just five everyday components and a few minutes of prep. The oven transforms basic ingredients into fudgy, chocolate-peanut butter bars that taste like a beloved bakery specialty.

It’s also incredibly versatile. Cut them into squares for a potluck, wrap individual bars for gifts, or serve them warm with a scoop of ice cream. The bars keep well, travel beautifully, and disappear fast.

Ingredients

• 1 box (18.3 oz) fudge brownie mix (plus the eggs, oil, and water called for on the box)

• 1 cup creamy peanut butter

• 1/2 cup powdered sugar

• 12 peanut butter cups, chopped

• 1 cup semi-sweet chocolate chips

Optional add-ins: 1 teaspoon vanilla extract, a pinch of flaky sea salt, and 2 tablespoons melted butter for the peanut butter layer.

Directions

1. Preheat oven according to the brownie mix package directions and lightly grease a 9×13-inch baking dish.

2. Prepare the brownie batter according to the package directions, then spread half of the batter evenly in the prepared dish.

3. In a small bowl, stir together the peanut butter, powdered sugar, and melted butter if using until smooth. Drop spoonfuls of the peanut butter mixture over the brownie batter, then scatter half of the chopped peanut butter cups on top.

4. Spread the remaining brownie batter over the top, then sprinkle with the chocolate chips and remaining peanut butter cups.

5. Bake according to the package directions, adding 5 to 8 minutes if needed, until the center is set and a toothpick comes out with moist crumbs.

6. Let cool completely before cutting into bars. Sprinkle with flaky sea salt if desired.

Serving Ideas

These bars are lovely served slightly warm with a scoop of vanilla ice cream or a glass of cold milk. For a cozy dessert plate, pair them with a cup of coffee, or wrap them individually as homemade gifts for bake sales and holiday trays.

Variations & Tips

• Brownie Tip: Don’t overbake—pull the bars when the center is just set so they stay fudgy.

• Peanut Butter Tip: Use creamy peanut butter rather than natural so the swirl layer stays smooth.

• Add-Ins: A handful of chopped peanuts or a drizzle of melted chocolate on top adds extra texture and decadence.

• Storage: Cover leftovers tightly and refrigerate up to 4 days, or freeze up to 3 months; a few seconds in the microwave brings back that fresh-from-the-oven fudginess.

Conclusion: Oven Baked 5-Ingredient Peanut Butter Cup Brownie Bars

This is the sort of recipe that earns a permanent spot in the dessert rotation—five ingredients, one pan, and a fudgy, chocolate-peanut butter bar that tastes like you fussed far more than you did. The rich brownie layers and creamy peanut butter cups make them special enough for a holiday gathering yet easy enough for an ordinary afternoon, and cutting them into bars means they travel beautifully to potlucks and bake sales. Keep them in your apron pocket for cozy weekends and last-minute cravings—and enjoy the fact that they stay fresh and delicious for days.