PAT short ribs dry and season with salt and pepper.
COAT a large, nonstick pan with olive oil. Sear the short rib pieces over medium-high heat for about 2-3 minutes on each side or until brown. Transfer short ribs to a bowl.
ADD onions to pan and cook over medium heat for approximately 3 minutes. Once onions are translucent, add garlic and cook for 1 minute; do not brown. Add Chianti, rosemary, beef broth and tomatoes to the pan one at a time, allowing liquid to partially evaporate before each addition (about 2 minutes).
RETURN short ribs to pan, including any juices that might have accumulated in the bowl. Cover and let simmer for 3 hours on low heat to complete the braising process. Remove short ribs from pan and boil the liquid until it is reduced by half, about 10 minutes.
RETURN short ribs to pan and heat thoroughly.
SERVE with potatoes or risotto and vegetables.