Method:

• Stir the yeast and sugar into the warm milk. Set aside for 10 minutes until frothy.
• In a mixing bowl or stand mixer fitted with the dough hook, add the flour, pinch of salt, melted butter and beaten egg and mix well for at least 2 minutes to form a soft, sticky dough. Cover with a clean, damp cloth and rest the dough for 10 minutes.
• Hand-knead the rested dough or mix with the dough hook for 2–3 minutes more, until it becomes smooth and supple. Cover and rest again for 20–30 minutes, or until increased in size by about half.
• Tip on to a lightly floured work surface and roll out to about 1.5cm thick.
• Cut out six to eight 8cm circles and place them on greased baking paper, reserving the offcuts. Cover with a clean tea towel and prove for 30 minutes–1 hour, until doubled in size.
• Fill a deep-sided saucepan two thirds full with oil (do not overfill). Heat it to 180°C or until a little piece of the reserved dough sizzles and rises to the surface and browns immediately.
• Working in batches, fry each doughnut for about 1½ minutes on each side, until golden all over, then carefully remove with a slotted spoon to a wire rack. Coat with extra sugar while warm.
• Put the apple sauce into a piping bag fitted with a medium, round piping nozzle, or cut the corner tip off a small, sturdy plastic bag. When cool enough to handle, push the piping nozzle (or use the tip of a knife to make a hole so that you can push in the plastic bag) into the centre of each doughnut and fill with apple sauce, then repeat with the custard.
• Serve drizzled liberally with the maple syrup.

Recipe adapted from Home Cookery Year (Quadrille)