Beat cream cheese and powdered sugar, fold in 1 cup whipped topping. Spread over cooled crust, refrigerate until set. In a bowl whisk together milk and both puddings. Let stand for 5 minutes or until slightly thickened. Spread over cream cheese mixture. Top with 3 cups whipped topping. Sprinkle with chocolate shavings. Refrigerate at least 2 hours before serving. Delicious served with ice cream.