The whoopie pie from Zingerman’s Bakehouse, in Ann Arbor, Mich., sports a chocolate glaze on its dense chocolate cake and is filled with Swiss buttercream filling. Featured in: Whoopie! Cookie, Pie Or Cake, It's Having Its Moment .. Ever heard of a whoopie pie? They're a bit like a macaroon but with a more cake-like texture. Hugely popular Stateside, the name comes from when Amish women would put them in farmers' lunchboxes and they'd supposedly shout 'whoopie' if they found one in their box!. 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.. The whoopie pie sold since last fall at Zingerman’s Bakehouse, in Ann Arbor, Mich., sports a chocolate glaze on its dense chocolate cake and is filled with Swiss buttercream filling.. Preheat oven to 180 C / Gas 4. Grease baking trays. Sift together the 250g flour, bicarbonate of soda,1/4 teaspoon salt, cocoa and 200g sugar.. 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"..