Preheat oven to 350 degrees F. Lightly grease a 8x8 inch or 9x9 inch baking pan, set aside.
BROWNIE LAYER: In a small microwave safe bowl melt the bittersweet chocolate and butter in 15 second intervals stirring after each until smooth and melted. In the bowl of a stand mixer beat together the eggs, sugar and vanilla until fluffy. Add in the flour, salt and chocolate mixture and mix just until combined. Spread into prepared baking pan. Bake for 30 minutes. Remove from oven and cool completely before spreading on the mint layer.
MINT LAYER: In a large bowl or the bowl of your stand mixer beat the butter and cream cheese until smooth. Mix in the mint extract and food coloring if desired. Slowly add in the powdered sugar and salt. Spread over cooled brownie layer and chill for 25-30 mintues.
CHOCOLATE TOPPING: in a small microwave safe bowl combine the chocolate chips and cream. Microwave in 15 second intervals stirring after each until smooth and melted. Spread carefully over the mint layer. Chill for 25-30 minutes or until chocolate is firm. Cut into squares. Store in the refrigerator.