Heat the oil in a pan. Fry steak for 2 mins on each side until brown. Remove steak to a plate, then throw the onion, garlic and oregano into the pan. Fry for 5 mins until starting to turn golden.
Tip the wine and tomatoes into the pan, then simmer for 10 mins until thickened and rich. Slice the steak into chunks, return to the pan with any juices, then simmer for a few mins to reheat. Serve with pasta, chips or some fried potatoes.