Mix together cookie mix, egg, and butter in a medium bowl.
Press into a 9x13 baking pan and bake in a 350 degree oven for 12 minutes. Cool to room temperature.
Remove lid and foil top from a can of frosting. Microwave for 30 seconds or until melted. Pour over the bars and spread to an even layer of frosting..
Top with sprinkles. Cut and enjoy!