In a large mixing bowl, whisk together the milk and instant vanilla pudding until well combined. fold in the Cool Whip.
Place a single layer of graham crackers in the bottom of a 9×13-inch pan.
Spread half of the pudding mixture on top of the crackers.
Layer another layer of graham crackers over the pudding mixture.
Then layer the other half of the pudding mixture on top of crackers. Top with a final layer of graham crackers.
Microwave chocolate frosting for 30 seconds and pour over top of eclairs cake.
Refrigerate for at least 4 hours or until set. slice and serve.