In a large oven proof dish fry onions in a little oil until they are translucent. Add the beef and fry until the beef is browned.
Stir in the flour then add the stock, tomato puree, carrots and any other vegetables such as potatoes, swede, cauliflower, garlic and balsamic vinegar.
Cover with a tightly fitting lid and place in a 170 C oven for around 2 hours - braising steak tends to be get more tender the longer you cook it.
Add pepper if necessary but you may find that the stock gives enough seasoning.