Rehydrate the mushrooms by soaking them in 1/2 cup of warm water for 30 minutes. Drain them well and reserve.
Preheat the oven to 325 degrees F. Season the veal shanks with salt and pepper. Dredge in flour, shaking off the excess. Reserve the flour.
Heat the oil in a large skillet set over medium-high. Brown the veal on both sides, then transfer to a casserole. Add the onions to the skillet and cook for 3 minutes; mix in the garlic and cook 1 minute more. Mix 3 Tbsp. of the reserved flour into the skillet; discard the rest.
While mixing steadily, slowly pour in the wine until a thick paste forms. Slowly mix in the stock and bring to a simmer; stir in the reserved mushrooms, chopped rosemary and then season with salt and pepper. Pour this mixture over the veal shanks.
Cover and bake for 2 hours, or until the meat is very tender and falling off the bone. Skim any fat from the surface of the veal before serving.
Note: Dried mushrooms are sold in small bags in the produce department. The brand used in this recipe was All Seasons Mushrooms.