Prepare brownie mix according to box instructions.
Add in 1/2 c. mini chocolate chips and mint extract, mixing until blended.
Bake at 350 degrees for 20-25 minutes in a greased 8-inch springform pan until a toothpick inserted 2-inches from sides comes out with moist crumbs.
Cool on a wire rack for 15 minutes.
Meanwhile, in a large mixing bowl, beat cream cheese and sugar until smooth.
Add in mint extract.
Beat in eggs, just until blended.
Fold in 1/2 c. mini chocolate chips.
Spread evenly over brownie layer.
Bake at 350 degrees for 35-40 minutes or until cheesecake is still slightly jiggly in the center when shaken.
Cool on a wire rack.
In a small saucepan on low heat, combine 12 oz. bag of chocolate chips and 1/3 c. heavy cream.
Cook and stir until chocolate is melted and smooth, and milk is well-incorporated.
Spread evenly over cooled cheesecake.
Enjoy!