Line a 9×13-inch baking dish with parchment paper, leaving extra parchment hanging over the sides to make it easy to lift out the frozen s’mores later.
In a medium bowl, whisk together the chocolate pudding mix, milk, and 1/2 cup Cool Whip until the mixture is smooth and creamy.
Arrange half of the graham cracker halves evenly on the bottom of the prepared baking dish.
Spread the pudding mixture into an even layer over the graham crackers. Place the dish in the refrigerator to chill while you prepare the next layer.
In another medium bowl, beat together the cream cheese and marshmallow creme until smooth and well combined. Fold in the remaining 2 cups of Cool Whip and a pinch of salt.
Spread the cream cheese mixture evenly over the chilled chocolate layer.
Place the remaining graham cracker halves on top of the cream cheese layer, pressing down gently.
Cover the dish with foil and freeze for at least 6 hours, or until the layers are firm enough to cut through.
Once frozen, use the overhanging parchment paper to lift the frozen s’mores out of the dish. Place them on a cutting board and, using the graham crackers as a guide, slice the s’mores into 12 squares. Trim away any excess frozen filling for clean edges.
Enjoy the frozen s’mores immediately, or store them in the freezer in a zip-top bag. If stored in the freezer, allow the sandwiches to soften at room temperature for about 15 minutes before eating.
Storage: Store in the freezer for up to 1 month. Allow to soften slightly before serving.