S2, E30: When Dr. Bellows invites himself and his wife to dine at Tony's, Roger and Tony know it's a trap. Tony asks Roger to bring a date too and tells Jeannie he's hired a sweet old lady to prepare the meal. Tony tries to get Jeannie out of the house but she hides in a teacup. Jeannie sees Kathryn, Tony's date, preparing a delicious Italian meal and is furious. Jeannie blinks and the meal becomes inedible. When she collapses the soufflé, Tony tells the invisible Jeannie in the kitchen that she's none too far. Dr. Bellows hears Tony apparently talking to the stove and decides to investigate. To make amends, Jeannie produces a delicious cake. Mrs. Bellows demands the recipe but Tony refuses on the ground it's an old family secret. She takes some cake home. After everyone except Tony eats the cake, they all revert to childhood. The next day, Mr. Fakeling of the National Food Bureau reports that the cake Mrs. Bellows brought to be analyzed contains an ingredient similar to a drug that restores youth. At home, trying to visualize Tony as a little boy, Jeannie blinks him into a Buster Brown outfit, just as Dr. Bellows and Fakeling arrive. Fakeling makes an enormous offer for the secret ingredient, but Tony maintains it got into the cake at the lab. Tony orders Jeannie, who never follows a recipe, to duplicate the cake. She produces one that resembles the first one, but Tony tastes it, and becomes a bearded old man. Jeannie pops out to look for her cook book.