1. Place aluminum foil baking cups in a lightly greased 12-cup muffin pan, and coat with cooking spray.
2. Process cookies in a food processor 30 seconds or until finely ground. (Yield should equal about 1 1/2 cups.) Transfer to a medium bowl. Process 1 cup candies 30 seconds or until finely ground. Stir ground candies and butter into ground cookies until combined. Divide crumb mixture among prepared cups, pressing firmly on bottom and two-thirds up sides of each cup. Freeze 30 minutes.
3. During last 10 minutes of freezing, let ice cream stand at room temperature.
4. Place ice cream in bowl of a heavy-duty electric stand mixer. Beat at low speed, using paddle attachment, 5 to 10 seconds or until just smooth enough to spread.
5. Spoon ice cream into crusts, filling completely full. Freeze 1 hour. Dollop each with about 2 Tbsp. whipped topping, and top with remaining 1/2 cup candies. Let stand 5 minutes before serving.