Fred Astaire & Ginger Chicken - S6-E20
Plot hole: Jack spends part of this episode clumsily teaching Karen basic steps of the fox trot for her wedding dance with Finster. However, in season 4, episode 16 ("A Chorus Lie") It is established that Karen and her husband Stan have, for years, performed an annual spotlight dance at their Valentine's party on Shelter Island. Later, she and Will are seen beginning a rather elegant fox trot to "Someone to Watch Over Me," complete with spins and a dip.
Answer: A history of the game can be found at http://www.fast-rewind.com/bacon.htm.
J I Cohen