Preheat oven to 350F.

In a bowl, combine chocolate cookie crumbs and butter. Press mixture firmly and evenly into the bottom and up the sides of a 9-inch pie plate. Bake for 8 to 10 minutes, or until the crust is firm. Let cool completely.

In a large mixing bowl, combine ice cream, whipped topping, and peanut butter. Pour half of the mixture into prepared crust.

Arrange Butterfinger Fun Size in a circular pattern and cover with remaining half of the ice cream mixture.

Cover and freeze for at least 2 hours or until firm. Before serving, allow to thaw for 5 to 10 minutes before cutting into slices. Serve with chocolate fudge sauce if desired.