1. Pour milk into large bowl. Stir in food color. Add pudding mixes. Beat with wire whisk 2 minutes or until well blended. Let stand 5 minutes. Gently stir in whipped topping.
2. Layer crushed cookies and pudding mixture in 3-quart bowl, beginning and ending with crushed cookies.
3. Refrigerate 1 hour or until ready to serve. Garnish as desired with shamrock candies.