Maine Whoopie Pie

• Chocolate Shells: 4 cups all purpose flour, 1 cup dark cocoa powder, 2 tsp salt, 2½ tsp baking soda, ½ cup unsalted butter unsalted, 2 cups sugar, 2 large eggs, ½ cup Crisco, 1 cup hot water, 1 cup soured milk, 1 tsp vanilla extract.
• Filling: 7 Tbsp marshmallow fluff, 4½ Tbsp vanilla extract, 4 Tbsp flour all purpose, 4 Tbsp milk, 4½ cups confectioner's sugar, 1¼ cups Crisco.
• Preheat oven to 350. In a large bowl, sift together the flour, cocoa powder, salt, and baking soda. Set aside. In a separate bowl, combine the butter, sugar, shortening, eggs, and vanilla extract with a hand or stand mixer. Add the hot water and sour milk to the butter mixture, and combine well. In stages, add the bowl of dry ingredients to the wet bowl, mixing well after each addition. Line a baking sheet with parchment paper. Drop about 3 tablespoons of batter onto the sheet, leaving 2" of space between each shell. Bake 10 minutes, and allow to cool several minutes on the sheet before removing to a rack to finish cooling.
• Sift the confectioner's sugar into a large bowl. Add all the remaining filling ingredients and mix on medium high until well combined and slightly fluffy. Scoop the desired amount onto an upturned chocolate shell, and lightly press a second shell on top. Makes 24 pies.