Don't let the butcher trim the fat off the lamb chops! Shred some of it and render it down in a heavy casserole. Peel onions and potatoes, scrape carrots. Cut the meat into 8 pieces; only excess fat is cut away. Bones need not be removed. Cut the carrots and onions in quarters. Toss the meat in the hot fat until its color changes; repeat with onions and carrots. Add stock and season carefully. Put whole potatoes on top. Simmer gently until the meat is cooked, approximately 2 hours. Pour off the cooking liquid: degrease it, and reheat in a saucepan. Check seasoning. Then swirl in butter, chives, parsley, and pour back over stew.