Heat oven to 180C/160C fan/gas 4 and line baking trays with parchment. Mix flour, cocoa, bicarb, sugar and a pinch of salt. Whisk the egg, oil and buttermilk together, then mix into dry ingredients with 75ml boiling water.. 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. The whoopie pie was moist and not overly sweet with great texture from the grated apple and the frosting complimented the pies perfectly. Of course, you could roll with your favorite buttercream as well and it would be equally delicious. I stored these in the fridge and then just took them out a bit before serving to knock the chill off since they had cream cheese frosting. I’m still not . 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".. I just tweaked the proportions a bit to make it able to stand on it’s own, and I think you’ll love this whoopie pie version. But it’s the filling that really takes these whoopie pies to the next level.. Pair each whoopie pie half up with another half based on size and shape. Place the filling in a piping bag with the end snipped off, and pipe 1-2 tablespoons sized dollops atop one of the halves. Sandwich with the other and press down slightly..