Trim the lamb of all fat, bone, and gristle. Cut into 2-inch cubes and sprinkle with thyme, salt, and pepper.
Heat 2 tablespoons of the olive oil in a heavy-bottomed pan. Add the lamb and sauté for 5 minutes. Sprinkle with salt and pepper, cook for 15 minutes, and set aside in a bowl. Put the wine in the pan, scrape up the bottom, and pour into the bowl of lamb. (You can prepare this much ahead of time and cover with plastic wrap until ready to use. Or you can prepare the whole dish ahead, and at serving time, reheat over a low flame for 10 minutes.)
Heat 2 tablespoons of the olive oil in the skillet. Add the onions, potatoes, garlic, orange rind, and bay leaves, and cook for 5 minutes. Add the lamb and the liquid. Cook, covered, for 40 minutes or until the lamb is tender (add more wine if necessary). Check the seasoning.
Remove the bay leaf and orange rind. Five minutes before serving add the olives. Garnish with parsley or fennel and serve.