Fondant potatoes

Preheat the oven to 180°C, gas mark 4. Cut 2 chunky lengthways slices from each potato, each about 2cm thick.

Melt the butter in a large frying pan with the oil and thyme sprigs and fry the potatoes for 8 minutes or until they are lightly browned on the underside. Turn and fry for a further 2 minutes. Transfer to a roasting tin or shallow baking dish with browned sides facing up. Add the stock to the frying pan, season and bring to the boil.

Pour the stock around the potatoes and cook in the oven on the shelf above the lamb for about 35 minutes, until very tender. Serve with the cooking juices spooned over.