Preheat the oven to 300°F.
Salt and pepper the shanks liberally on all sides. Dredge in flour until well coated.
Heat the olive oil in a large pot or Dutch oven until shimmering. Add the shanks, searing on all sides.
Turn off the heat. Pour in the beer, scraping to deglaze the pan. Add the remaining ingredients.
Cover the pot and add to the oven, cooking for 3 ½ hours or until the beef is fork-tender. About every hour of cooking, turn the beef over.
Once the beef is done, remove from oven, remove the bones and any large pieces of fat.