Season the steaks with salt and pepper.
Heat the butter in a large frying pan over high heat, add the steak and cook for 30 seconds each side to seal. Remove from the pan.
Add garlic and sherry; deglaze the pan with the red wine. Add the beef stock and cook for 2-3 minutes, add the sour cream and cook for a further minute.
Return the steak to the pan, along with any of the juices and cook until done to your liking.
Place the ham into a medium frying pan and cook until crisp. Remove from the pan. Add oil and fry the egg, keeping the yolk soft.
To serve, place the steak in the centre and a fried egg on top. Place the crispy ham on the egg and pour the sauce over. Serve immediately with crisp green salad.