A whoopie pie is essentially two pies-two round pieces of chocolate cake--with a cream filling in the middle. Oreo makes an Oreo Cakester and Hostess makes the Suzy Q, but those are not real Whoopie Pies, although they can be eaten in a pinch.
I grew up close to Pennsylvania Dutch country (o.k. that's what we called it), and as a child, we often stopped at the Pennsylvania Dutch open markets for all kinds of treats. Whoopie Pies were a very special favorite of mine and one I could only obtain depending on the adult with me. Dietary concerns. The real whoopie pies were two small flattish chocolate cakes with a filling made from Crisco mixed with vanilla, egg whites and sugar, or dare I say it, pure butter mixed with sugar, and egg whites and maybe a little vanilla. Those were the days.
We often spent summers in Maine, and the whoopie pie was there, too. I remember the Maine version as good--well, what kid doesn't think a cream filled chocolate cake-pie is good--but not as good as the Amish whoopie pie. They didn't seem as rich, but don't get me wrong, they were tasty! Probably not made with as much lard, crisco or butter. The chocolate cake was different, too.
The Epicurious recipe for Whoopie Pies uses Droste brand Dutch-process cocoa for the reicipe for a richer chocolate flavor and the filling recipe uses marshmallow cream. The NY Times article has a recipe adapted from Zingerman's Bakehouse in Ann Arbor, MI. With a little more digging, I found an article on the History of Whoopie Pies in What's Cooking America. The article mentions the 1930s cookbook Yummy Book by the Durkee Mower Company, the manufacturer of Marshmallow Fluff. Needless to say the filling was more like marshmallow. I think the whoopie pie goes further back, so if you find something, let me know.
O.K. Whoopie Pies are a lot like Moon Pies, in case you're from another part of the country. I hail from near Lancaster County, so they'll always be those mouth-watering Whoopie Pies to me--and probably made with vegetable shortening or butter filling. Yes, that was the old crisco or the rich butter from local cows. Zing--straight to the arteries, but what a treat!
Here's a filling recipe from that 1930s cookbook
Whoopie Pie Filling:
1 cup solid vegetable shortening*
1 1/2 cups powdered sugar
2 cups Marshmallow Fluff**
1 1/2 teaspoons vanilla extract
* Butter may be substituted for all or part of the vegetable shortening, although traditional Whoopie Pies are made with vegetable shortening only
What a great comfort food for these troubled times.