01 -
Spray a 9"-x-13" baking dish with cooking spray. In a large bowl, whisk together the chocolate pudding mix, milk, and cocoa until smooth.
02 -
In another large bowl, beat marshmallow crème and cream cheese together until smooth.
03 -
Line the bottom of the prepared baking dish with a layer of graham crackers. Spread half the marshmallow mixture over the graham crackers and sprinkle with 2 cups of mini marshmallows. Spread half the chocolate pudding mixture over the marshmallow layer. Repeat two more times with the remaining graham crackers, marshmallow mixture, 2 cups mini marshmallows, chocolate pudding mixture, and dark chocolate chips.
04 -
Refrigerate the assembled lasagna, covered, until cold and set, at least 2 hours.
05 -
Remove the lasagna from the refrigerator. Spread Cool Whip evenly on top. Heat the hot fudge sauce in the microwave until just pourable but not too hot. Pour the hot fudge over the lasagna and top with crushed graham crackers, Hershey's chocolate pieces, and the remaining mini marshmallows before slicing and serving.