I think it’s Chuck Jones’s “Broom-Stick Bunny.” I think I have a real fondness for Halloween stories where trick-or-treating turns disastrous, whether it’s for Bugs in this cartoon or Margaret O’Brien in Meet Me In St. Louis (one of the few movies that portrays kids playing old-fashioned Halloween games, where they literally try to be evil). It is kind of a spooky concept.
The “Witch Hazel” character had already appeared in an even funnier cartoon, “Bewitched Bunny,” where she was voiced by Bea Benaderet. By the time they made this follow-up, Benaderet had quit doing voices for WB (she did most of the female characters in the ’40s and early ’50s), so in “Broom-Stick Bunny” she was replaced by June Foray, who did a great job. (Foray was never able to match Benaderet’s work as Granny in the Tweety cartoons, though.)
But Foray had already used a similar voice for another character called “Witch Hazel,” in the Disney Halloween cartoon “Trick Or Treat.” Jones told Foray that Disney couldn’t sue because Witch Hazel is an actual product, so nobody owned the name. Anyway, here’s another Halloween cartoon adventure, Donald Duck and Witch Hazel in “Trick Or Treat.”
Also, via the excellent Chuck Jones blog, here are some layout drawings Jones made for the end of “Broom-Stick Bunny” (they were for the animators, as a guide to how the scene should look; at his best, Jones’s layout drawings were some of the most expressive in the business. That’s why his best cartoons had such terrific, memorable character poses and expressions):