Preheat the stove to 2200. In a heavy, 25 to 30 cm frying pan, heat the olive oil until a light smoke forms.
Put in the lamb, 4 to 5 pieces at a time, and sear at a moderate temperature. When the cubes are well browned on all sides, place them in a heavy 21/2 to 3 quart Reindl. Next, pour off all but a thin layer of fat from the roasting pan and set it aside. Season the lamb with rosemary, garlic, salt and pepper and dust with flour, turning the meat with a wooden spoon to coat the cubes as evenly as possible with the spices and flour. place the Reindl in the upper third of the oven and brown the lamb, uncovered, for 8 to 10 minutes, turning two or three times. When all the flour is well absorbed and the lamb cubes have a light crust, remove the Reindl from the heat and reduce the temperature to 175 °C. Pour the vinegar into the prepared roasting pan and quickly bring to a boil over high heat for a minute or two, stirring in any drippings clinging to the roasting pan. Next, add the chicken broth, bring to a boil and pour the liquid over the lamb placed in the Reindl. cover the Reindl and place in the center of the oven. Steam the lamb for 1 hour, or until tender when tested with the tip of a sharp knife. (If