Thread the steak onto metal skewers and rub with olive oil. Place on a baking tray and cover completely with the rock salt. Place in the fridge for 1 hour. Wipe with absorbent paper to remove the rock salt and sprinkle with pepper. Heat a char-grill pan or barbecue over high heat. Add the skewers and cook for 7 minutes each side for medium rare or until cooked to your liking. Serves 4.