Two answers required. Viewers of NYPD Blue briefly saw Andy Sipowicz's bare butt in the season 1 episode "The Final Adjustment," and Connie McDowell's bare butt in the 2003 episode "Nude Awakening" (the latter led to an FCC fine that the U.S. Supreme Court later struck down). Name both actors.
(The former played Homer Simpson in the fictitious TV movie "Homer S.: Portrait of An Ass-Grabber" while the latter was Quinn Fabray's mom on Glee.)
Dennis Franz; Charlotte Ross