Chocolate Eclair Cake

1 box graham cracker crumbs
12 oz container Cool Whip
2 packages vanilla instant pudding
3 cups milk

Topping:
2 oz. unsweetened chocolate, melted
3 tsp vanilla
4 T. milk
1 1/2 cup powdered sugar

Mix pudding and milk with mixer. Blend in Cool Whip. Layer graham crackers in 13X9 pan. Spread 1/2 mixture over crackers. Spread another layer of cracker crumbs. Spread remaining mixture and end with another layer of cracker crumbs. Frost with topping. Refrigerate overnight.