After piercing the lamb and inserting garlic cloves, then lightly salting and peppering the outside, the lamb leg is encrusted in a paste made up of fresh garlic, fresh rosemary, Dijon mustard, lemon zest and juice, white wine and Panko crumbs. The paste forms a very flavorful crust on the outside of the lamb as it roasts and encases the lamb and most of its juices inside.