Prepare and bake one package cookie mix as directed, using butter and the egg.
Allow cookies to cool completely.
For each ice cream sandwich, place slightly softened ice cream between two cookies.
Dip sandwich into melted chocolate, coating the outside edge of the sandwich.
Shake sprinkles on chocolate.
Cover with plastic wrap and return to freezer until frozen.
(They tasted great right after they were made, however if you let them sit in the freeze for a day, the cookies soften and the ice cream hardens more- making them a little easier to eat!)