WHISK 1 1/4 cups evaporated milk and pudding mix in medium bowl until well blended. Pour into crust.
MICROWAVE 2 cups marshmallows and remaining 1/4 cup evaporated milk in medium, uncovered, microwave-safe bowl on HIGH (100%) power for 30 to 45 seconds; stir until smooth. Let stand for 15 minutes. Gently fold in whipped topping. Spoon marshmallow mixture over chocolate layer; smooth top with spatula.
REFRIGERATE for 2 hours or until set. Top with remaining 1 cup marshmallows and morsels.
• For a gooey S’more topping, place chilled pie on a baking sheet. Preheat broiler. Place baking sheet with pie on rack 6 inches from broiler unit (pie top should be at least 4 inches from broiler unit). Broil for 30 seconds or until marshmallows are light brown and morsels are shiny. Watch carefully as browning occurs very fast! A handheld kitchen butane torch can be used as well.