Classic Whoopie PiesMakes 8IngredientsFor the pies:125g (4 ½ oz) butter or margarine, softened200g (7oz) light brown sugar1 large egg, beaten350g (12oz) plain flour50g (2oz) cocoa powder5.25ml (1 ¼ tsp) Dr Oetker Bicarbonate of Soda1.25ml (½ tsp) salt250ml (9fl.oz) low fat butter...