Wipe the meat and trim neatly. Crush the peppercorns in a basin using the end of a rolling pin, with a pestle and mortar, or on a board under a heavy weight.
Using the fingers, press the crushed peppercorns into the surface of the meat on both sides. Heat the butter and oil in a frying pan and when frothing add the steaks. Cook fairly quickly for the first few moments and turn the steak – the initial hot frying seals the peppercorns on to the surface of the meat. Lower the heat and cook the steaks for the required amount of time, allowing 8–10 minutes for rare to medium-done. Turn the meat for even cooking, then lift from the pan and serve with any buttery juices poured over.