The lobster should be cut in two down the center. Remove all the meat from the lobster, including the claws: retain the shell for serving. Cut the meat into chunks. Heat the butter until foaming and quickly saute the lobster chunks in it, until just cooked but not colored. Warm the whiskey slightly, then pour it over the lobster and set fire to it. Add the cream, mix with the pan juices, and taste for seasoning. Put back into the half shells and serve hot.