A link to a very short clip of Alfred Hitchcock on the Dick Cavett show in 1972, making an atrocious pun, in his studiedly lugubrious way.
This prompts an observation. In an extended and illuminating series of interviews with François Truffaut, published in French as Le Cinéma selon Alfred Hitchcock (1967, English translation with the collaboration of Helen G. Scott), Hitchcock is reported as saying "Some films are a slice of life. Mine are a slice of cake."
This has always struck me as wrong - a slip that occurred when the book was translated from the French back into English without reference to the original tapes. It should surely be: "Some films are a slice of life. Mine are a piece of cake." That makes sense. It's witty and memorable and positions Hitchcock against the realist documentary tradition.
You saw it here first. But I've just found out that you can download twelve hours of the original conversation between the two directors here. So you can find out for yourself. Let me know if I'm wrong.