I've found that the best method for frosting, drizzling, and storing these cookies is as follows:
Place cookies (as many as you can fit) on a baking sheet. Frost those cookies. Next, drizzle the cookies with the melted Andes mint chocolate candies. Place the baking sheet in the freezer for 3-4 minutes, or in the fridge for 4-6 minutes until chocolate cools completely. You should now be able to place your frosted cookies in a large tupperware, stacking them with sheets of wax paper or parchment paper to separate each layer of cookies. Repeat with remaining cookies. Cover the tupperware and store in the fridge until ready to serve. About 10-15 minutes before serving take them out and let them sit at room temperature.