He acted in the sports comedy movie Caddyshack II (1988). In 1990 and 1991, Mason again was on Broadway, this time with his successful two-act show Brand New, which ran for 216 performances at the Neil Simon Theatre, which won him his second Outer Critics Circle Award. Critic Clive Barnes of The New York Post praised the “brilliant” comic and his “totally new from top to tuchis” humor. Critic Mel Gussow of The New York Times remarked on the “exact meeting” between performance and material in which Mason engaged in a comic attack on everyone, including himself, cutting them all down to size.
In 1992, Mason won a Primetime Emmy Award for Outstanding Voice-Over Performance for his voice-over of Rabbi Hyman Krustofski in The Simpsons episode
“Like Father, Like Clown”, making him the first guest star to win an Emmy for his role. Mason has also appeared in The Simpsons episodes “Today I Am a
Clown”, “Once Upon a Time in Springfield”, “The Ten-Per-Cent Solution”, “At Long Last Leave”, and “Clown in the Dumps”; the latter episode focuses upon Rabbi
Krustofski’s death and its effects on his son, Krusty the Clown.