In a saucepan, combine chocolate with 2 tablespoons of the milk; heat over low heat, stirring, until chocolate is melted. Beat sugar into the cream cheese; add remaining milk and the chocolate mixture. Beat until smooth. Fold whipped topping into the chocolate mixture until blended.
Spoon filling into crust then freeze until firm. If desired, garnish with additional whipped topping and cookie crumbs or chocolate curls. Take out of freezer and let stand at room temperature for about an hour before serving. Store in freezer.
Calories per serving: 326
Fat per serving: 19g