Heat the oil in a heavy frying pan. Add the beef joint and sear on both sides for several minutes.
Chop the vegetables and place in a slow cooker along with the other ingredients. When ready, add the beef. Fill the empty tomato tin up with water and add that in.
Cook on low for about six hours (until you can shred the beef).
Loosely shred with a fork and serve immediately with rice, potatoes or warm bread.