Make the Mint Frosting
- In the bowl of a stand mixer fitted with the paddle attachment, beat the softened butter on high speed for 3–4 minutes, until light in color and smooth in texture. Scrape down the sides of the bowl as needed.
- Add the powdered sugar one cup at a time, mixing thoroughly after each addition. Scrape the bowl frequently to ensure even mixing.
- Once the sugar is incorporated, add the heavy whipping cream, peppermint extract, and food coloring. Begin mixing on low speed to avoid splatter, then increase to high and beat for 3–4 more minutes until the frosting is fluffy and spreadable.
- Spread the mint frosting evenly over the cooled brownie layer, smoothing the top with an offset spatula or the back of a spoon. Place the frosted brownies in the fridge while you prepare the ganache to help the mint layer firm up slightly.
Make the Ganache
- In a microwave-safe bowl, heat the heavy cream for about 1 minute until hot but not boiling. Meanwhile, place the chocolate chips and butter in a separate medium bowl.
- Pour the hot cream over the chocolate and butter. Let it sit undisturbed for 3–4 minutes to allow the chocolate to soften. Then whisk slowly until completely smooth and glossy. If chunks remain, microwave in 20–30 second intervals and whisk again.
- Allow the ganache to cool slightly—just enough that it’s pourable but not hot. Pour it over the chilled mint frosting layer, spreading evenly with a spatula. Work gently to avoid disturbing the layer below.
- Refrigerate the finished brownies for at least 30 minutes or until the ganache is set and firm to the touch. This helps all layers hold their shape when sliced.
Storage
Store leftover brownies in an airtight container in the refrigerator for up to 3 days. For best flavor and texture, allow them to sit at room temperature for 10–15 minutes before serving. These brownies are also freezer-friendly—wrap tightly and freeze for up to 1 month.
