I've previously included Condiment King in the Batman the Animated Series Super-Post, where I said this:
The Condiment King, aka Mitchell Mayo, is a comic relief villain that first appeared in the Batman: The Animated Series episode "Make 'Em Laugh" (1994). He first appeared in comics in Birds of Prey #37 (January 2002), also in a comic relief role, although chronologically he first appeared in Batgirl: Year One #8 (September 2003), where his costume and equipment has a much more home-made vibe.
Except for a couple issues of Final Crisis Aftermath: Run! (2009), those were the extent of his comic appearances. He belongs to an important-but-overlooked class of villains that's good for cameos and brief fight scenes but not much else. And there's nothing wrong with that.
It's in that regard that he makes a post-Rebirth appearance, locked up in Arkham in Batman #9 (October 2016):