From the Odd Things Found On Internets Dept: Addams Family breakfast cereal commercial. This would have been from the early or mid-90s. Sometime after the movies came out. I have very specific memories of sitting around the kitchen at Pru's old house trying to figure out what the "mysterious flavor" (which they actually described on the box as "mysterious flavor") in this cereal was. Sadly, no mention of "mysterious flavor" in the commercial. Found via So Good.