Make the vinaigrette with the olive oil and red wine vinegar and leave to one side.
For the steak, heat the oil and butter in a heavy-based frying pan.
Cook the steak should take about five minutes (for medium) turning and colouring on both sides. When ready remove from the pan and allow to rest for a few minutes.
Add the tomato quarters, olives and caperberries to the pan and quickly sauté.
Deglaze the pan with the red wine and add the contents of the pan to the vinaigrette.
Heat a frying pan until hot then add the olive oil and potatoes, garlic and rosemary. Sauté until golden.
Wilt the spinach in a hot frying pan.
Serve the steaks on top of the spinach and potatoes. Pour over a little of the vinaigrette with the tomatoes and olives.
