Gardenia appeared in many other Simon plays including "God's Favorite", in a role written specially for him by the playwright. He is perhaps best known as Archie Bunker's loquacious, ever-singing, culinary buff neighbor Frank Lorenzo on the CBS perennial, "All in the Family".
Gardenia spent a considerable portion of his career playing huffy but good-hearted police officers, detectives, and station captains in TV movies including "Cops" (1973), "Muggable Mary: Street Cop" (1982), "The Dark Mirror" (1984) and "Brass" (1985), and films such as "Heaven Can Wait" (1978). His final film appearance was as the father of Joe Pesci in "The Super" (1991).