RHM Foodservice (Marlow, Bucks) says filling a doughnut with lemon curd, then garnishing with caster sugar and cinnamon, is a simple way to make a spicy lemon doughnut.

Robertson’s Fruit Preserves or Golden Shred Marmalade (available from RHM Foodservice) can be used for more traditional jam-filled doughnuts.

McDougalls Complete Custard Mix can also be piped into doughnuts, while a doughnut cream twist can be made by deep-frying the doughnut mix in cream horn moulds then filling with whipped cream.