Make the brownies according to the package and allow them to fully cool.
While the brownies are cooling make the peppermint buttercream icing by combining butter, powered sugar, milk and peppermint and mixing on low until creamy.
Once brownies are fully cool, spread the peppermint icing on top of the brownies. Place in the refrigerator to harden.
Make the chocolate topping. In a double boiler on low melt the butter, then add the chocolate chips and light corn syrup. Stir continuously until the chocolate is melted. Be careful not to over cook it. Then spread the chocolate on top of the peppermint icing.
Top with crushed candy canes. Chill and then serve and ENJOY!