Add the whisky to the pan used to cook the steaks, and heat over a very high heat for 1 minute to boil off the alcohol. A word of warning: the whisky is likely to burst into flames, so if this worries you, have a large lid handy to whack on the pan. Add the stock and reduce until thick, then pour in the cream. Reduce again, and deglaze the pan, using a heat-proof spatula to scrape and stir together any caramelised pieces stuck to the bottom. When the sauce is thick and well reduced, pour in any juices from the resting meat and stir.