Born in Pennsylvania Dutch country and named in Roxbury, Massachusetts, the Whoopie Pie has fans all over the country. But no state loves it more than Maine. Mainers went all out and declared it their Official Maine State Treat in 2011. And why not? This sensational sandwich of black chocolate cake filled with fluffy vanilla creme plays havoc with our self-control. And now, thanks to our friend Allen’s authentic recipe, we can whip up the real deal, the divine Maine Whoopie Pie, in the comfort of our own kitchens. How did Allen unlock the secret to the ultimate Whoopie Pie? He started with the master recipe his sister-in-law developed when she was a student…