On a cutting board, finely chop cookies, 2-3 at a time. Place butter in small microwave-cooker. Microwave on HIGH 30 seconds or until melted. Mix in cookie crumbs. Press crumb mixture onto bottom of a springform pan. Freeze 15 minutes
Cut candy bar into 4-5 pieces; wrap in plastic wrap and freeze 10 minutes. Chop into small pieces.
Cut ice cream container apart to expose block of ice cream. Cut half of ice cream into 1-inch-thick slices.
Arrange ice cream slices over cookie crust, cutting pieces to fit. Spread into a smooth layer. Sprinkle with chopped candy bar.
Top with remaining ice cream prepared the same way as first layer. Smooth top with spreader. Cover with aluminum foil.
Freeze 3 hours or overnight.
Attach open star tip to a decorator. Fill tube with whipped topping and set aside. Run knife around edge of ice cream cake.
Release collar from pan. Lightly frost top and side of ice cream cake with remaining whipped topping.
Decorate with whipped topping using decorator. Top with sprinkles. Freeze 1 hour or overnight. Once whipped topping is frozen lightly cover cake with plastic wrap.
To serve, cut into wedges. (If cake was frozen overnight, place in refrigerator 10 minutes before slicing.)