These Triple Layer Fudgy Mint Oreo Brownies are a chocolate lover’s dream come true, with rich, gooey brownie layers, creamy mint frosting, and crunchy Oreo pieces all stacked up in one delicious treat. The mix of fudgy texture, refreshing mint, and the classic crunch of Oreos makes these brownies an absolute crowd-pleaser.
I love making these brownies for gatherings because they always get everyone’s attention—and they never last long on the dessert table! What’s fun about them is how each layer adds something different: the dense brownie base, the minty middle that’s just cool enough, and the Oreo toppings that bring a little crunch. They’re easy to slice and share, which I really appreciate when I’m baking for friends or family.
My favorite way to enjoy these brownies is slightly warmed with a glass of cold milk nearby—simple but so good. If you want a little extra, I sometimes sprinkle some crushed Oreos on top right before serving for that added Oreo goodness. These brownies remind me of cozy nights where dessert is the best part of the day, made even better with the classic combo of mint and chocolate.
Key Ingredients & Substitutions
Butter: Unsalted butter gives control over salt levels and rich taste. You can swap it for margarine or coconut oil, but the flavor and texture might change slightly.
Cocoa Powder: Use unsweetened cocoa powder for that deep chocolate flavor. Dutch-processed cocoa works great here for a smoother taste.
Oreos: Classic Oreo cookies add a crunchy minty charm. If unavailable, try chocolate sandwich cookies or gluten-free Oreos for dietary needs.
Peppermint Extract: It brightens the frosting with mint flavor. Candy canes (crushed) or mint syrup can be used but adjust sweetness accordingly.
Green Food Coloring: Optional but gives the frosting a fresh minty look. You can skip it if you prefer all-natural, the taste stays the same.
How Do You Get Brownies Fudgy Without Overbaking?
Overbaking is the biggest enemy of fudgy brownies. Here’s how to avoid it:
- Keep your oven at the right temp (350°F/175°C) and avoid opening the door too often.
- Check for doneness by inserting a toothpick near the center. It should come out with moist crumbs, not dry.
- Cool the brownies completely in the pan. They firm up as they cool, giving that perfect fudgy texture.
Also, don’t overmix your batter; this keeps brownies tender, not cakey. I like to stop stirring as soon as ingredients are combined to keep them dense and rich.
Equipment You’ll Need
- 9×13 inch baking pan – I use this size because it gives even layers and fits perfectly in my oven.
- Mixing bowls – for combining the brownie batter and frosting easily.
- Microwave-safe bowl – handy for melting butter quickly.
- Whisk or electric mixer – makes mixing smooth and saves time, especially for the frosting.
- Rubber spatula – helps spread the batter and frosting evenly in the pan.
- Cooling rack – to speed up cooling and prevent sogginess.
- Measuring cups and spoons – for accurate ingredient portions.
- Cover or plastic wrap – keeps the brownies fresh in the fridge.
Flavor Variations & Add-Ins
- Chocolate chips or chunks – fold into the brownie batter for extra chocolate bites.
- Different mints – add crushed peppermint candies or mint chocolate pieces to the frosting for more mint flavor.
- White chocolate drizzle – melt white chocolate and drizzle on top for a sweet, creamy touch.
- Nut add-ins – sprinkle chopped nuts like walnuts or pecans over the frosting for crunch.
Triple Layer Fudgy Mint Oreo Brownies
Ingredients You’ll Need:
For the Brownie Base:
- 1 cup (2 sticks) unsalted butter
- 2 cups granulated sugar
- 4 large eggs
- 1 tablespoon vanilla extract
- 1 cup all-purpose flour
- 1 cup unsweetened cocoa powder
- ½ teaspoon salt
- ½ teaspoon baking powder
- ½ cup crushed Oreo cookies
For the Mint Frosting:
- ½ cup unsalted butter, softened
- 1½ cups powdered sugar
- 2 tablespoons heavy cream or milk
- 1 teaspoon peppermint extract
- 3-4 drops green food coloring (optional)
For Topping:
- 1 cup crushed Oreo cookies
- Whole Oreo cookies for decoration
How Much Time Will You Need?
This recipe takes about 15 minutes to prepare the batter and frosting, around 25-30 minutes to bake, and at least 1 hour to chill the brownies before slicing and serving. Plan for about 2 hours total to get the best results.
Step-by-Step Instructions:
1. Prepare the Brownie Base:
Preheat your oven to 350°F (175°C). Grease a 9×13 inch baking pan or line it with parchment paper for easy removal. In a microwave-safe bowl, melt 1 cup of butter. Stir in the sugar right away while the butter is still warm, then let it cool a little. One at a time, add the eggs, mixing well after each. Stir in the vanilla extract.
In another bowl, whisk together the flour, cocoa powder, salt, and baking powder. Slowly add these dry ingredients into the wet mixture and stir until just combined. Gently fold in ½ cup of crushed Oreos for a tasty texture surprise.
Pour the batter into the prepared pan, spreading it evenly. Bake for 25-30 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs. Remove the pan from the oven and allow the brownies to cool completely.
2. Make the Mint Frosting:
While the brownies cool, beat the softened butter in a large bowl until smooth and creamy. Gradually add powdered sugar, alternating with the heavy cream or milk. Beat after each addition to keep it fluffy. Stir in the peppermint extract and add green food coloring if you’d like a fresh minty look. Continue mixing until the frosting is smooth and easy to spread.
3. Assemble and Chill:
Spread the mint frosting evenly over the cooled brownies. Sprinkle the remaining 1 cup of crushed Oreos evenly on top. For a pretty finish, place whole Oreo cookies spaced out over the frosting. Cover the pan and refrigerate for at least 1 hour to let the frosting set nicely.
4. Serve:
Once chilled, cut the brownies into squares. You can serve them cold from the fridge or let them sit at room temperature for a few minutes before serving. Enjoy the rich, fudgy brownies with cool mint frosting and crunchy Oreos!
Can I Use Frozen Butter for the Brownies?
It’s best to use melted butter at room temperature for the brownie batter to mix smoothly. If your butter is frozen, thaw it completely before melting to ensure even mixing and texture.
How Should I Store Leftover Brownies?
Store leftover brownies in an airtight container in the refrigerator for up to 4 days. This keeps the mint frosting fresh and the brownies fudgy. Let them come to room temperature for a few minutes before serving for the best flavor.
Can I Make These Brownies Ahead of Time?
Yes! You can bake the brownies and frost them a day in advance. Just cover them tightly and keep them refrigerated. This actually helps the flavors meld together and makes slicing easier.
What If I Don’t Have Peppermint Extract?
You can substitute with mint syrup or a few drops of pure mint oil, but start with less since these can be stronger. Alternatively, skip the mint extract and just enjoy classic fudgy Oreo brownies.