Wash the lamb and pat dry. Sprinkle the shanks all over with the cumin, salt and pepper. Roll the shanks in flour to coat well and pat off any excess.
Heat the oil in a large Dutch oven over medium-high heat until almost smoking. Cook the shanks, in batches if necessary, until golden brown all over, about 10 minutes. Remove and reserve. In the same oil, saute the onions and carrots until they begin to brown, about 6 minutes. Add the garlic and saute about 4 minutes longer. Remove with a slotted spoon, and then carefully pour off all the fat.
Place the shanks back in the pan. Cover with the browned vegetables and the oregano stems and pour in the wine. Bring to a boil over high heat and reduce the liquid by half. Stir in the tomato paste, chicken stock and bay leaves, cover and bring to a boil.
Transfer to the oven and bake 1 1/2 hours, or until tender. A fork plunged into the thickest part should slide out easily. Remove from the oven, lift out the meat and keep warm. Lift out the vegetables and discard.
Skim and discard the fat from the stock in the pan. Bring to a boil over high heat. Stir in the tomatoes and oregano leaves and remove from the heat. To serve, in each soup bowl place a lamb shank. Top with the hot broth and sprinkle with the cheese.
c.1997, M.S. Milliken & S. Feniger, all rights reserved