500g Maris Piper potatoes (left over from Saturday), cut into even-sized pieces
1 large egg, beaten
125g plain flour, plus plenty of extra for shaping
splash of olive oil
knob of butter, for frying
few rosemary leaves, optional
Steam the potatoes for 15-20 mins until tender. Mash well, ideally with a ricer, which will give fluffier gnocchi. Add the egg and some seasoning, mix briefly with a fork, then sift over the flour and bring together to make dough. It should feel dry to the touch but not crumbly. Add more flour if needed, then knead a few times on a floured work surface.
Bring a large pan of water to the boil. Split the dough into tennis-ballsized pieces, then roll into fingerwidth ropes. Dust with a little flour, then cut into bite-sized pieces. Boil in batches for about 1 min or until they bob to the surface. Lift from the pan with a slotted spoon and leave to cool in a single layer on a large plate or tray. Drizzle the oil over the cooled gnocchi and toss gently with your hands to coat.
When ready to serve, heat the butter in a frying pan, add the rosemary (if using), then fry the gnocchi in a few batches until crisp and golden. Keep warm and serve with the lamb.