Either buy a piece of lamb with six loin chops on it and ask the butcher to bone, roll and cut the joint into six, or, alternatively, buy six loin chops and with a small sharp knife remove the T-bone at the base. Then roll and tie them up individually yourself. Dip both sides of the meat in seasoned flour. Heat the butter in a frying pan, add the meat and brown gently on both sides for about 15–20 minutes. Lift the chops from the pan and place in a large casserole.
Peel the button onions, leaving them whole. Add to the hot butter in the pan and fry quickly, turning often to brown them slightly. Add these to the lamb along with a good pinch of rosemary which has been crushed. Pour away all but about 1 tablespoon of the fat in the frying pan, taking care to leave as much of the sediment behind as possible. Add the wine and bring back to the boil, stirring and scraping to mix the sediment into the sauce. Pour this over the meat, add the chopped parsley, sliced mushrooms and scraped new potatoes – cut in half if large.
Cover with a buttered paper and a lid, place in the centre of a moderate oven (180°C., 350°F., Gas Mark 4) and bake for 1 hour. About 10 minutes before the cooking time is completed add the peas, re-cover and complete cooking time. Remove the string from around the lamb noisettes before serving.