Season the veal with salt and pepper and dredge in flour. In heavy dutch oven over medium high heat, brown veal in olive oil until browned on all sides (5-10 minutes). Transfer to a plate and keep warm. Add the onions, carrots, and garlic to the dutch oven and saute for 5-10 minutes until onions are translucent and vegetables begin to brown. Add wine, stock, tomatoes, rosemary and thyme and bring to a boil. Add veal, cover, and put in oven to cook until meat is tender, about 1 ½ to 2 hours. Check pan occasionally and add more stock if necessary to keep level about half way up the side of the shanks.
Transfer veal to bowl and discard rosemary. Use immersion blender to roughly puree liquid in dutch oven keeping some of the vegetables intact. Add back veal and warm until heated through. Add salt and pepper to taste.
Serve over polenta or risotto and sprinkle with the gremolata.