Injecting jam into round doughnuts was one of the best bakehouse jobs. Once jammed, we rolled the doughnuts in sprinkled sugar, which Dad laid out on copies of The Daily Telegraph. One day, my granddad, Papa, played a trick on Jack, a local allotment holder, when he injected English mustard into a doughnut. When Jack bit into it he turned bright red and spat it out. A smooth jam filling goes down much better!