To Make Whoopie Pie Filling: Beat egg white and mix with the milk, 1 teaspoon vanilla and 125g of the icing sugar. Mix well then beat in the butter and the remaining sugar. Beat until light and fluffy.. You can play thousands of free online games including action, life, puzzle, skill and sports games. Also there are a lot of interesting tags you can browse like tower defense games, room escape games or cooking games.. A whoopie pie is a sweet baked item which is a cross between a soft biscuit, a cake and a pie. It is made up of two round pieces of cake-like biscuits (cookies) which are sandwiched together with a sweet, creamy filling. Other names given to these sweet delights have included hucklebucks, gobs and BFOs (big fat Oreos).. 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.. 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!. Double Chocolate S’mores Whoopie Pies: A duo of chocolate and marshmallow-y frosting pair up in the middle of these campfire-free, s’mores-inspired whoopies. (via Girl Versus Dough ) 11..