These whoopie pies are flavoursome and festive, bursting with fruit and spices. With their spicy ingredients and red and silver balls, they embody all the joy of a Christmas cake in a few bites.
Preheat the oven to 180°C/350°F/Gas 4. Line two baking trays with baking parchment. For the cakes, whisk the butter, sugar and vanilla until fluffy. Whisk in the egg.
In a separate bowl, sift the flour with the bicarbonate of soda, salt and ground spic