Mint chocolate brownies are a dream come true for mint chocolate lovers. A fudgy chocolate brownie layered with mint buttercream frosting, smooth chocolate ganache and topped with mint Oreo cookies. These decadent chocolate mint brownies are perfect dessert for St. Patrick’s Day or to satisfy your mint chocolate cravings!
Ingredients for Mint Chocolate Brownies
- Unsalted butter: You can also use salted, just omit any additional salt.
- Chocolate chips: Dark or semisweet chocolate chips.
- Granulated sugar: For sweetness.
- Brown sugar: Light brown sugar adds moisture and extra fudginess.
- Salt: Enhances the flavor and contrasts the sweetness.
- Eggs: Room temperature.
- Espresso powder: Espresso powder enhances the chocolate flavor. The brownies won’t taste like coffee at all, I promise.
- Vanilla extract: Vanilla extract enhances the chocolate flavor as well.
- All-purpose flour: Level the measuring cups!
- Dark cocoa powder: Dark cocoa powder gives the best chocolate flavor.
Mint buttercream frosting
- Unsalted butter: Room temperature for easy creaming.
- Powdered sugar: No need to sift unless there are lumps.
- Vanilla extract: Vanilla extract adds vanilla flavor that compliments the mint.
- Mint extract: Use regular mint or spearmint extract rather than peppermint extract for this recipe.
- Salt: A bit of salt contrasts the sweetness.
- Green gel food coloring: Optional but recommended. I love using Americolor or Chefmaster. The green gives the buttercream layer a cool, minty green look!
- Heavy cream: Heavy cream or heavy whipping cream works perfectly well.
- Chocolate: Use semisweet or dark chocolate chips.
- Heavy cream: Heavy cream or heavy whipping cream. It will not work with regular milk.
- Butter: A bit of salted butter creates a smooth, shiny chocolate layer.
- Mint Oreo cookies: Roughly chopped.
How to Make Fudgy Chocolate Brownie Layer
The bottom layer of these brownies is my fudgy chocolate brownie recipe! I recommend using an electric hand mixer to make the brownie batter. You can also use a stand mixer fitted with a paddle attachment.
- Melt chocolate chips and butter in the microwave in 30 second intervals.
- Whip eggs, granulated sugar, brown sugar, eggs, vanilla extract, salt, and espresso powder.
- Pour in chocolate mixture and mix on low speed until combined.
- Add all-purpose flour and dark cocoa powder. Mix on low speed until just combined.
- Pour brownie batter into a prepared 9×13 baking pan.
- Bake at 350 degrees F for approximately 25-30 minutes.
- Remove the brownies from the oven and allow to cool to room temperature.
How to Make Mint Buttercream Layer and Chocolate Ganache
Mint buttercream frosting
To make the mint layer, I recommend using a stand mixer for the best results. You can use a paddle attachment or a whisk attachment based on your personal preference. If you do not have a stand mixer, you can also use an electric hand mixer.
- Whip room temperature butter for about 5 minutes until light, fluffy, and pale in color.
- Add in half of the powdered sugar and mix on the lowest speed until the sugar is combined with the butter. Then add the remaining powdered sugar and continue to mix on low speed.
- Add mint extract, vanilla extract, and salt and continue to mix on low until combined. Add a drop or two of green gel food coloring if desired.
- Slowly drizzle in the heavy cream. Be sure to scrape the sides and bottom of the bowl after this step to ensure everything is well mixed.
- Turn the mixer to medium-high speed and whip the buttercream for about 3-5 minutes.
There are two ways to make the chocolate ganache! Microwave or stovetop!
- Microwave: Combine chocolate, heavy cream, and butter in a microwave-safe bowl. Heat in 30 second intervals, mixing in between, until the chocolate melts and the ganache is smooth.
- Stovetop: Heat heavy cream in a small saucepan until bubbles form at the edge of the pan. Pour the hot cream over the chocolate and butter and allow it to sit for a few minutes. Mix until the chocolate melts and the ganache is smooth.
Mint Chocolate Brownies Recipe Tips
Prepare the pan
I have found that the best way to prepare baking pans for brownies is with nonstick cooking spray and parchment paper. Spray the 9×13 pan with nonstick cooking spray. Use two pieces of parchment paper that are longer than the length and width of the pan. Position the parchment paper in the pan so that the brownies can be easily lifted out of the pan!
Whip eggs and sugar for a few minutes
One of the keys to getting perfect texture to the brownies is to whip the eggs and sugar for a few minutes until the mixture becomes light and fluffy. As there are no leavening agents in the recipe, this creates the rise in the brownies and creates the perfect texture.
Cool brownie layer completely before adding mint frosting
Before you spread on the mint buttercream layer, you want to ensure that the brownies are completely cooled. Use an offset spatula to spread the mint buttercream to create an even layer. Similarly, be sure your chocolate ganache is slightly cooled before spreading onto the mint buttercream layer.
Cutting the brownies
To make perfect cuts in your brownies, remove the brownies from the pan by lifting up on the parchment paper. Use a straight-edge knife. Press the knife down into the brownies and pull the knife out of the side of the brownies. Pulling the knife up will create messy edges.
Storing and serving
Store the brownies in an airtight container in the refrigerator or at room temperature for 2 to 3 days. The brownies are best served at room temperature.
Mint Chocolate Brownies
- Electric hand mixer or stand mixer fitted with a whisk attachment & paddle attachment
- 9×13 baking pan
Fudgy Chocolate Brownie Layer
- 1 cup unsalted butter
- 1 ¼ cups chopped bittersweet or semisweet chocolate or chocolate chips
- ½ cup granulated sugar
- 1 cup brown sugar
- 3 eggs room temperature
- 2 tsp vanilla extract
- 1 tsp salt
- 1 tsp espresso powder
- 1 cup all purpose flour
- ½ cup dark cocoa powder
Mint Buttercream Layer
- 1 cup unsalted butter room temperature
- 2 ½ cups powdered sugar
- ½ tsp vanilla extract
- 1 tsp mint/spearmint extract
- ¼ tsp salt
- 1 drop green gel food coloring
- 2 tbsp heavy cream
- 1 cup semisweet chocolate chips
- ¼ cup heavy cream
- 2 tbsp salted butter
- 12-15 mint chocolate cookies (Mint Oreos or Thin Mints) chopped
Fudgy Chocolate Brownie Layer
- Preheat oven to 350° F. Prepare a 9×13 baking pan with cooking spray and parchment paper. The parchment paper should go up the sides of the pan so the brownies are easily lifted out of the pan.
- In a microwave-safe bowl, combine unsalted butter and bittersweet/semisweet chocolate chips. Microwave in 30 second intervals, mixing in between, until the chocolate and butter are melted and fully combined.
- In a large mixing bowl, combine granulated sugar, brown sugar, eggs, vanilla extract, salt, and espresso powder. Using an electric hand mixer, mix on low speed until the ingredients combine and then turn the mixer to high speed and whip for 2 to 3 minutes until the mixture is light and fluffy.
- Slowly drizzle in the chocolate mixture, mixing on low speed until the chocolate is fully incorporated with the egg mixture.
- Add in the all-purpose flour and dark cocoa powder. Mix on low speed until the dry ingredients are fully incorporated with the wet ingredients. Do not overmix. Use a spatula to scrape the sides of the bowl to ensure that all the ingredients are well combined.
- Pour the brownie batter into your prepared 9×13 baking pan and spread evenly.
- Bake for approximately 25-30 minutes or until a toothpick inserted in the center of the brownies comes out with wet crumbs and not batter. Cool the brownies in the pan completely before adding on the mint buttercream layer.
Mint Buttercream Layer
- In a large mixing bowl with an electric hand mixer or the bowl of a stand mixer fitted with a whisk or paddle attachment, add in room temperature unsalted butter. Whip the butter for 5 minutes on medium-high speed, scraping down the sides occasionally. The butter will be light, fluffy, and pale in color.
- Add one half of the powdered sugar and mix on the lowest speed setting until fully combined. Add remaining powdered sugar and continue to mix on low until incorporated.
- Add vanilla extract, mint extract, and salt and mix on low until combined. Add a bit of green gel food coloring if desired.
- Increase speed to medium on the mixer and slowly drizzle in the heavy cream. Scrape the sides of the bowl occasionally to ensure the frosting is well mixed.
- Turn the speed on the mixer to high and whip for an additional 3-5 minutes until the buttercream is light and fluffy.
- Spread the mint buttercream onto the cooled brownies using an offset spatula to create an even layer. Chill the frosted brownies for about 30 minutes.
- Combine chocolate chips, heavy cream, and salted butter in a microwave-safe bowl. Heat in the microwave in 30 second intervals, mixing in between until the chocolate is mostly melted.
- Continue to mix until the chocolate ganache is smooth. Set aside for 10 minutes to cool the ganache. (*See notes for stovetop method).
- Pour the cooled ganache on top of the mint buttercream layer and spread evenly using an offset spatula.
- Sprinkle the top of the chocolate ganache with chopped mint chocolate cookies (Mint Oreos or Thin Mints work great).
- Chill the brownies for an additional 30 minutes. Lift up on the parchment paper to remove the brownies from the pan. Cut into squares.