In a large bowl, whisk together the pudding mix and milk until smooth and thickened.
Grab a 9×13-inch baking dish. Start with a layer of graham crackers on the bottom
Spread half of the pudding mixture over the crackers, smoothing it with a spatula.
Add another layer of graham crackers, then the remaining pudding mixture.
Finish with one more layer of graham crackers on top.
Microwave the can of chocolate frosting for 20–30 seconds,
spread it evenly over the top layer of graham crackers.
Cover the dish with foil or plastic wrap and refrigerate for at least 6 hours