When lamb is golden brown on all sides, remove to 2-quart casserole or stew pot. Add onion and carrot to hot lamb fat in skillet and saute over moderate heat until golden brown. Stir in tomatoes and liquid, bring to boil and scrape in coagulated pan juices with wooden spatula. Pour over ribs in casserole. Add garlic, bay leaf, thyme, salt and pepper and 2 cups water.
05Bring to boil, then gently stir in lentils. Add enough additional boiling water to come just to level of lentils. Bring to boil, cover, reduce to simmer and cook steadily but gently for about 2 hours or until lentils and lamb are tender. Add boiling water as needed during cooking and stir gently every half-hour or so.06Adjust seasonings, adding a few drops of vinegar if you like.07This can be served with rice. One cup of raw rice cooked in boiling salted water will be about right.