1. Toss the onions, tomatoes, and garlic in a little oil, salt and pepper separately, and roast separately in a 400 degree oven until browned and slightly caramelized. 2. Season the shanks with salt and pepper, and lightly dust with flour. Sear on all sides in a preheated dutch oven or braising pan. Remove shanks from pan, and add half the roasted onions, and tomatoes, and all of the garlic. Place the shankson top of the vegetables, and then pour the wine over everything 3. Braise, covered, in a 350 degree oven or until tender. 4. Remove the meat and puree the sauce. Taste and adjust seasoning. 5. To serve, spoon some of the sauce on top of the shanks and then top with the remaining onions, and diced roasted tomatoes.