Bakers at the University of Maine Dining Services serve up an average of 20,000 whoopie pies, with some four different flavors, each year on campus. Not that anyone’s counting.  On Wednesday, Sept. 28, the popular sandwich-size cake with a sweet frosting inside becomes the official state treat. At Hilltop Dining, chefs, cooks, bakers, staff and read more UMaine celebrating state treat with Whoopie Pie Mountain