Cookies and Cream Brownies

Cookies and Cream Brownies take boxed brownie mix up a notch with Oreo cookies inside and out, all with a sweet marshmallow frosting and drizzle of fudge sauce. 

Love Cookies and Cream? Try these Cookies and Cream Cupcakes, cookies, monkey bread, popcorn, or donuts too. 

Why You’ll Love these Cookies and Cream Brownies

If you want Oreo brownies, this is the way to have them! The Oreos in the batter turn soft like the moist brownies after they’re baked.

Marshmallow fluff frosting is slathered on top with some extra chopped Oreo cookies. Top that all off with a simple fudge sauce and you, my friends, have got yourself the ULTIMATE OREO BROWNIES! Every bite is sure to have some Oreos!

I first made these cookies and cream brownies in a 12-inch foil pizza pan from the dollar store, which makes it a super fun shape, but I decided to re-make it into a regular 9×13-inch pan to keep it classic. You will need a few more Oreos to cover the pizza pan, if you decide to go that route.

Still need convincing? You’ll also love these cookies and cream brownies because they’re:

• Easy to Make: Grab a box of brownie mix, package of Oreos, and a few other simple ingredients to make these ultimate Oreo brownies. It’s so easy!
• Full of Chocolate:  From the dark chocolate brownies to the quick fudge topping, this Oreo dessert will satisfy your chocolate cravings.
• Sweet and Creamy: If you love the taste of marshmallows, then you’ll love the marshmallow creme inside the fluffy-sweet frosting.

Ingredients You’ll Need

*NOTE: Full ingredient amounts and instructions are in the printable recipe card at the end of the post.

• Oreo Cookies – Regular or Double Stuf. (The inspiration for this cookies and cream combo!)
• Dark Chocolate Brownie Mix – I love Duncan Hines. You can use your favorite brownie mix, but I feel the dark chocolate compliments the black cocoa in the Oreos best.
• Egg(s) – As listed on the box to make the brownies.
• Water – As listed on the box to make the brownies.
• Oil – As listed on the box to make the brownies.
• Shortening – This keeps the frosting white. If you don’t like shortening you can substitute it with coconut oil instead. Use refined coconut oil, if you don’t want any coconut taste. Another alternative would be to just use butter, but the frosting will be more ivory/off-white (like in this recipe). Choose a light colored butter, like Land O’Lakes, if this bothers you.
• Butter – This adds to the frosting’s flavor.
• Marshmallow Creme – Flavors the frosting to make it taste just like the Oreo filling!
• Powdered Sugar – To thicken and sweeten the frosting.
• Vanilla Extract – To enhance the flavor of the frosting.
• Chocolate Chips – For the fudge topping. (High quality semi-sweet chocolate chips are preferred.)
• Light Corn Syrup – Smooths and shines the fudge topping, and also helps it stay soft-set (doesn’t harden completely).

How to Make the Oreo Brownies

NOTE: The full ingredient amounts and instructions are in the printable recipe card at the end of the post.

• Preheat the oven to 350 degrees Fahrenheit. Lightly grease a 13×9-inch baking pan with cooking spray or line with parchment paper, leaving a couple inches of overhang to lift the dessert out of the pan.

• In a large bowl, mix together the brownie mix, egg(s), water, and oil well.
• Place 15 Oreos in the bottom of the prepared pan.
• Pour brownie batter over and around the Oreos to evenly fill the pan. Gently spread even with a spatula. (NOTE: It may be easier to spread the batter into the pan and then top with the Oreos so they don’t slide around, but I’m not totally sure if the brownie batter will cover the Oreos completely this way.)

• Bake at 350˚F for 20-23 minutes. (Check doneness with a toothpick.) Remove from oven and cool completely.

How to Make the Marshmallow Frosting

While the brownies are cooling, make the marshmallow frosting.

1. Beat the shortening and butter together in a large bowl with an electric hand mixer. 
2. Mix in the marshmallow creme and vanilla. 
3. Slowly mix in powdered sugar. 
4. Mix until smooth. Set aside.

How to Make the Fudge Topping

Once the brownies and frosting are made, all that’s left to do is make the fudge topping.

• Combine the ingredients for the fudge sauce in a microwave safe bowl. Heat in the microwave for 30 seconds.
• Stir, and add hot water if needed, for a thinner drizzle. (I didn’t need it, but the option is there.)

Assembling the Cookies and Cream Brownies

Once all the elements are made it’s time to assemble the Oreo brownies.

1. Spread the marshmallow frosting evenly over the cooled brownies.
2. Top with chopped or quartered Oreo cookies.
3. Drizzle with fudge topping. Allow fudge to cool down and set slightly (will still be somewhat soft) before cutting and serving.

Serving and Storing

• Cut brownies into 15 pieces and serve. (If you used parchment paper you can lift the whole dessert out of the pan with the overhanging paper, then place it on a cutting board and cut it.)
• Tightly cover leftovers in pan with plastic wrap or foil. Alternately store in an airtight container.
• Store at room temperature for up to 3-4 days.

Substitutions 

• Want to make it like Little Debbie’s Cookies and Cream Brownies? Try the frosting from this recipe instead.
• Prefer a homemade brownie? Try my fudgy brownies recipe.
• No Shortening: Use refined coconut oil (no coconut taste) or additional butter in its place.

These Cookies and Cream Brownies should really come with a warning label: DO NOT MAKE ALONE! You will easily devour the whole pan yourself. I don’t suggest doing that, but these are dangerously delicious! It’s a good thing I had my slice and dropped the rest of these at my neighbors’ houses. I’m craving them by just looking at the pictures! Enjoy!

If You Make This Recipe, Please Rate and Review it in the Comments Below. THANKS!

*Originally published as Oreo Fudge Brownie Pizza on 10/9/2014. Post updated August 2024.