1. Combine chocolate chips and milk in medium microwave-safe bowl.
Microwave at MEDIUM (50%) 1-1/2 minutes; stir. If necessary, microwave at MEDIUM an additional 15 seconds at a time, stirring after each heating, just until chips are melted when stirred.
2. Beat in cream cheese with whisk or spoon until mixture is well blended and smooth. Cool just to room temperature. Gently fold 2-1/2 cups whipped topping into chocolate mixture; spoon into crust.
3. Cover; freeze until firm. Garnish with whipped topping and fruit, if desired. Makes 8 servings.