Pat veal pieces dry with kitchen roll. Season with ¼ teaspoon salt and the pepper. Heat oil in a large casserole pot over high heat. Working in batches, add veal and brown on all sides, about 4 minutes per batch. Transfer veal to a plate.
Lower heat to medium. Add mushrooms and shallots to casserole. Saute until shallots are just golden, about 5 minutes. Stir in flour. Add veal, beer, vinegar, thyme and the remaining salt. Bring to the boil. Add carrots; cover. Lower the heat and simmer until veal is tender, about 1 hour 15 minutes.
Transfer veal, carrot and mushrooms to serving dish. Boil sauce until reduced to about 300ml. Pour over veal.