Season the beef, then sear on all sides in small batches over high heat in olive oil, remove and set aside. Include the garlic in the final batch.
Add 1 C of the chianti and bring to a boil, deglazing the pan. Reduce slightly, then return all the beef and the garlic to the pan, stir in the broth, tomatoes, tomato paste, thyme, bay leaf, and peppercorns, and return to a boil.
Cover and place in 250-degree oven for 2 hours, or until the beef is tender. Remove from oven, add the remaining chianti, and simmer for 20-30 minutes, until the sauce is thickened.
Plate over polenta and serve. Alternative, cool, refrigerate overnight, reheat and serve.
Source: adapted from foodiewithfamily.com, italymagazine.com