Combine graham cracker crumbs, sugar, and melted butter in a large bowl to create a graham cracker mixture.

Press the mixture firmly onto the bottom of a 9x13 inch baking dish. Refrigerate until ready to use.

In a bowl, beat together the softened cream cheese, sugar, and milk until well combined.

Gently fold in 8 ounces of thawed Cool Whip until no streaks remain.

Spread the cream cheese mixture evenly over the chilled graham cracker crust.

In a large bowl, whisk together the instant chocolate pudding mixes and 3 1/4 cups of cold milk until well blended and thickened. Let it sit for 5 minutes to thicken further.

Spoon the thickened chocolate pudding evenly over the cream cheese layer.

Refrigerate the dessert for at least two hours to allow it to set.

When ready to serve, spread the remaining 8 ounces of thawed Cool Whip evenly over the pudding layer.

Optional: Grate or shave a Hershey's bar over the top for garnish.

Cut into squares and serve chilled.