Growing up homemade whoopie pies were a treat. From the vantage point of a 10-year old they seemed rather simple. Why didn't we have them more often? Well turns out that Mom just made them look that way. What I didn't see was the amount of time it took to make the little cakes from scratch, wait for them to cool, whip up the filling and then assemble. Efforts such as this are what make mothers "moms."
Traditionally made with a fluffy vanilla-whipped filling surrounded by two round chocolate cakes these cookie-sandwiches are often said to be of northern New England or Amish-County Pennsylvania origin. According to Nancy Baggett in her All American Cookie Book, the treat has been traced back to the Depression era. Her source, Peter Schlichting of New Hampshire says that "the Berwick Cake Company, located it the Roxbury section of Boston...seems to have been the first t make them...a retired employee has recalled that the firm began whoopie-pie production in 1926." In fact if you grew up in New England or New York these may remind you of a high-class Drake's Devil Dogs.
I've made my mother's recipe several times but I'll be devil dogged if I can find it in my IBC. So recalling the recipe from memory and flipping through a few cookbooks I determined that I was not going to use hydrogenated vegetable shortening. Well I did end up using it--a trans-fat free Crisco. I also needed to mix it up with two different fillings, traditional vanilla and peanut butter (quelle surprise!).
The choice of cocoa powder is important here as the contrast between the filling and the cake creates a heightened, smoky, chocolaty taste. Typically I have Dutch processed cocoa powder on hand. Although I've tried many including Droste and Valrhona but my go-to is Pernigotti. Keep in mind that Dutch-processed is treated with an alkali to neutralize its acids. Due to this it does not react with baking soda, so it must be used in recipes calling for baking powder. It has a reddish-brown color, mild flavor, and is easy to dissolve in liquids.
Chocolate Whoopie Pies
4 cups flour
2 tsp. baking soda
1 cup Dutch-processed cocoa
2 cups sugar
1 cup shortening
1 cup milk
1 cup warm water
2 tsp. vanilla extract
Instructions: In a mixing bowl, combine the flour, baking soda, cocoa and salt. Mix well and set aside. In another bowl combine the sugar shortening and eggs. Beat 2 minutes. Add the dry ingredients to the egg mixture. Now add the milk and warm water and beat for 2-3 minutes at medium speed. Add vanilla extract and beat again. These "cakes" cook like cookies. Drop by rounded tablespoon onto an non-stick cookie sheet. Keeping uniformity is important. Bake for 10-12 minutes at 375 degrees until the center of the cookies spring back when lightly pressed. Remove from cookie sheet and cool on a wire rack.
Assembly: Spread a generous amount of filling on the bottom of a completely cooled cookie. Top with another.
Notes on storage: I learned the hard way that these little cakes don't keep too long particularly if you stack the unfilled cakes together. If you can't bake early in the day and fill them later on you could assemble and in turn wrap them in plastic wrap. They keep quite well in the fridge for several days in this method.
Vanilla Cream Filling
2 egg whites
2 1/2 tsp. vanilla extract
4 tblspns flour
4 tblspns milk
4 cups confectioner's sugar
1 1/2 cups vegetable shortening
Instructions: Beat the egg whites until stiff. Set aside. Working quickly combine the other ingredients and beat several minutes at high speed. Fold in the stiff egg whites
Peanut Butter Filling
2 tblspn unsalted butter
3/4 cup creamy peanut butter
3 1/2 cups confectioner's sugar
1/2 cup milk
Instructions: At medium speed mix the butter and peanut butter together. Add confectioner's sugar and milk. At high speed mix until well blended, light and fluffy.