To Prep: Preheat oven to 350°F (175°C) and line a 9-inch square baking dish with parchment paper.

Place chocolate chips in a large heat-safe bowl. In a separate microwave-safe bowl, melt the butter. Pour the melted butter on top of the chocolate chips and let sit for 1-2 minutes, then whisk together until melted and smooth.

Add in the granulated sugar, brown sugar, eggs, and vanilla extract until well combined.

Add the flour and salt, mixing until just combined.

Pour the batter into the prepared baking dish and spread evenly. Bake for 35-40 minutes, or until a toothpick inserted in the center comes out with only a few moist crumbs. Let cool completely before frosting.

In the bowl of a stand mixer (or in a mixing bowl, using an electric hand mixer) beat the softened butter until creamy.

Gradually add in the powdered sugar, milk, peppermint extract, and green food coloring, mixing until smooth and fluffy.

Spread the mint frosting evenly over the cooled brownies.

In a small saucepan or microwave-safe bowl, warm the heavy cream until just hot (but not boiling).

Pour the warm cream on top the chocolate chips and let sit for a minute, then stir until smooth and melted.

Gently spread the ganache on top of the mint frosting.

Chill the brownies in the fridge for 15 minutes, or until the ganache is completely set.