Lamb Roasted over Potatoes

For me, roast lamb is always meant leg of lamb, but shoulder is equally succulent, if a little fatty—don’t overlook it. You can use either leg or a shoulder here. A shoulder will probably only feed four people because of the bones and fat, whereas a leg will feed six people. A long leg will have had the pelvic bone removed by the butcher, so make sure that he secures the meat with string to make a compact shape. It will take 20 to 30 minutes longer to roa