01 - Preheat oven to 350°F. Line a 9-inch square baking pan with parchment paper, leaving overhang for easy removal.
02 - Melt 1/2 cup plus 2 tablespoons butter. In a large bowl, whisk melted butter and sugar until combined. Add eggs and vanilla, mixing well.
03 - Sift in flour, cocoa powder, and salt. Stir until just combined. Spread batter evenly in prepared pan.
04 - Bake for 22-25 minutes until a toothpick inserted in center comes out with moist crumbs. Cool completely in pan.
05 - Beat softened butter until creamy. Gradually add powdered sugar, milk, peppermint extract, and green food coloring; beat until smooth and spreadable.
06 - Spread mint cream evenly over cooled brownies. Refrigerate for 15 minutes to set.
07 - Melt chocolate chips and 2 tablespoons butter together until smooth using microwave or double boiler.
08 - Pour glaze over mint layer, spreading evenly. Refrigerate for at least 30 minutes until set. Remove using parchment overhang, cut into squares, and serve.