Whip together instant hot chocolate mix and one tub of cool whip and pour it into the pie crust.
In a separate bow, fold the marshmallow fluff into the other tub of whipped cream and pour on top of the hot chocolate layer. Don't be alarmed if it isn't smooth and creamy, it's fine.
Place in the freezer for at least 3-4 hours or overnight to firm up before eating.
Before serving, shave chocolate bits on top or sprinkle on the chocolate chips if you’re using those and finish with a sprinkle of crushed candy canes.