1 cup firmly-packed brown sugar
1/4 cup unsweetened cocoa
2 cups all-purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1 teaspoon salt
1 teaspoon pure vanilla extract
1 cup milk
Whoopie Pie Filling (see recipe below)
In a small bowl, stir the vanilla extract into the milk. Add the dry ingredients to the shortening mixture, alternating with the milk mixture; beating until smooth.
Drop batter by the 1/4 cup (to make 18 cakes) onto prepared baking sheets. With the back of a spoon spread batter into 4-inch circles, leaving approximately 2 inches between each cake. Bake 15 minutes or until they are firm to the touch. Remove from oven and let cool completely on a wire rack.
Make Whoopie Pie Filling. When the cakes are completely cool, spread the flat side (bottom) of one chocolate cake with a generous amount of filling. Top with another cake, pressing down gently to distribute the filling evenly. Repeat with all cookies to make 9 pies. Wrap whoopie pies individually in plastic wrap, or place them in a single layer on a platter (do not stack them, as they tend to stick).
To freeze, wrap each whoopie pie in plastic wrap. Loosely pack them in a plastic freezer container and cover. To serve, defrost the wrapped whoopie pies in the refrigerator.
Makes 9 large whoopie pies.
Some people prefer just using the Marshmallow Fluff right out of the jar and not making the below filling. Your choice.
1 cup solid vegetable shortening*
1 1/2 cups powdered (confectioner's) sugar
2 cups Marshmallow Fluff**
1 1/2 teaspoons pure vanilla extract
* Butter may be substituted for all or part of the vegetable shortening, although traditional Whoopie Pies are made with vegetable shortening only
** Marshmallow Creme may be substituted.
In a medium bow, beat together shortening, sugar, and Marshmallow fluff; stir in vanilla extract until well blended.
According to whatscookingamerica.net:
Whoopie pies are considered a New England phenomenon and a Pennsylvania Amish tradition. They're one of Maine's best known and most loved comfort foods. Mainers will even claim that they were weaned on whoopie pies. In Maine, these treats are more like a cake than a pie or a cookie, as they are very generously sized (about hamburger size). they're so hug that you'll want to share one with a friend. A big glass of milk is almost mandatory when eating a whoopie pie.
A whoopie pie is like a sandwich, but made with two soft cookies with a fluffy white filling. Traditional whoopies pies are made with vegetable shortening, not butter. The original and most commonly made whoopie pie is chocolate. but cooks like to experiment, and today pumpkin whoopie pies are a favorite seasonal variation.
The recipe for whoopie pies has its origins with the Amish, and in Lancaster county, Pennsylvania, it is not uncommon to find roadside farm stands offering these desserts. Amish cooking is about old recipes that have fed families for generations, with no trendy or cross-cultural fusions or mixtures. These cake-like whoopie pies were considered a special treat because they were originally made from leftover batter. According to Amish legend, when children would find these treats in their lunch bags, they would shout "Whoopie!"
The question of how the Amish dessert got to be so popular in New England probably is addressed in a 1930s cookbook called Yummy Book by the Durkee Mower Company, the manufacturer of Marshmallow Fluff. In this New England cookbook, a recipe for Amish Whoopie Pie was featured using Marshmallow Fluff in the filling.
According to the Marshmallow Fluff website:
The origins of Marshmallow Fluff actually go back to 1917. Before WWI, a Sommerville MA man named Archibald Query had been making it in his kitchen and selling it door to door, but wartime shortages had forced him to close down. By the time the war was over, Mr Query had other work and was uninterested in restarting his business, but he was willing to sell the formula. Durkee and Mower pooled their saving and bought it for five hundred dollars. Having just returned from France, they punningly renamed their product "Toot Sweet Marshmallow Fluff" but "Toot Sweet" didn't stay on the label for long. The situation of "no customers, but plenty of prospects" didn't last long either.
An early receipt still in the company's scrap books records the sale in April, 1920 of three one gallon cans to a vacation lodge in New Hampshire. The price at the time was $1.00 a gallon! The door to door trade gained a reputation among local housewives that eventually placed Fluff onto local grocers shelves. Retail trade spread from there to the point where in 1927 they were advertising prominently in Boston newspapers.
Durkee-Mower became a pioneer in radio advertising when in 1930 they began to sponsor the weekly "Flufferettes" radio show on the Yankee radio network, which included twenty-one stations broadcasting to all of New England. The fifteen minute show, aired on Sunday evenings just before Jack Benny, included live music and comedy skits, and served as a steppingstone to national recognition for a number of talented performers. The show continued through the late forties.
Each episode ended with a narrator reporting that Boswell had disappeared to continue work on his mysterious book, which was assumed to be a historical text of monumental importance. On the last episode the Book-of-the-Moment was revealed. It was a collection of recipes for cakes, pies, candies, frostings and other confections that could be made with Marshmallow Fluff, appropriately entitled the Yummy Book. The book has been updated many times since then, and the most recent version is thirty-two pages long.
The main difference between recipes for New England Whoopie Pie and Amish Whoopie Pie, seems to be the use of commercial Marshmallow Fluff/Creme in the New England version. Otherwise, most recipes are basically the same.