Whoopie Pie Cake Recipe 2 cups of Marshmallow FLUFF (or you can melt some marshmallow along with a little bit of milk) 1 1/2 tsp of vanilla extract Cream the butter and the powdered sugar . KAISER 12-Cup Whoopie Pie Baking Pan 38 x 27 cm Creativ Very Good Non-Stick Coating Short Baking Time for Sweet and Savoury Recipes. L.D. 71, officially known as "An Act to Designate the Whoopie Pie as the State Dessert", read "The whoopie pie, a baked good made of two chocolate cakes with a creamy frosting between them, is the official state dessert".. Fall in love with this easy recipe for whoopie pies. Two light discs of chocolate sponge sandwich a fluffy vanilla buttercream filling. Perfect for cake sales, packed lunch treats or making friends at the office!. Beat the butter and sugar in an electric mixer on high speed until light and fluffy. Beat in the egg, followed by the vanilla and buttermilk. Reduce speed to low, add dry ingredients and beat until combined.. Whoopie! This list of 25+ Whoopie Pies is so fantastic! Are Whoopie Pies cookies, cakes, or pies? One thing is for certain, Whoopie pies are delicious sweet sandwiches filled with scrumptious frosting filling..