'The Further Adventures of the Joker' is what you're thinking of. Great anthology. I was reminded more of another entry in that, the one called 'Masks', where - and I'm doing my damnedest not to give anything away to those who haven't read it, 'cause it's a damn fine read - the Joker unmasks the Batman - and then the Batman gets back at him by UNMASKING THE JOKER... Brrrr.