Heat the butter and oil in a frying pan and fry the
onion until soft but not colored.
Scrape to the side of
the pan, increase the heat and fry the steaks on both
sides, until cooked as required. Remove the meat from
the pan and keep warm.
Add the whiskey to the pan
and set alight; when the flames have subsided, pour on
the cream and mix with the onion and meat juices.
Bring
to the boil, add salt and pepper to taste, add the
parsley and pour the sauce over the meat. Serve
immediately, garnished with watercress.