The dish Kelly served Uncle Bentley for dinner is called truffle in aspic. Truffles in aspic was a pork tenderloin stuffed with truffles that was then suspended in a special savory gelatin made from meat stock. It could be built in a simple loaf pan or an intricate jello mold and it was always served cold. Aspic recipes were popular for a short period of time in the 50's.
A running gag in this episode is that the young girls keep saying that Ronnie Burns "practically supports his mother and father". Ronnie was, of course, the adopted son of George Burns and Gracie Allvn, who were major stars on both radio and on their own TV show. Ronnie had a relatively small role on his parents' shows, and had little success in showbiz beyond that.