Reduce the stock by two-thirds, and keep warm.
Trim the lamb, removing all the fat, and clean the bones to the eye of the meat. Seal the lamb in
To prepare the coating, mix the breadcrumbs, herbs and salt and pepper together. Brush the outer surface of the lamb with the beaten egg and then cover with the breadcrumb mixture, pressing well to bind the crumbs.
Place the lamb in a roasting tray and cook in an oven set at 190°C/375°F/gas 5 for about 7 minutes or until the meat is pink. Remove the meat from the oven and leave it to rest for 4 minutes.