According to Netflix, a "Jenny sandwich cookie" is a cookie with a sandwich, usually consisting of two parts and a center sandwich. The term is commonly associated on the Internet with a video called "Jenny's Cookie Machine". This video shows a machine that automatically creates a sandwich cookie by combining the cookie and the center automatically. The name of the machine is "Jenny", hence the name "Jenny Cookie Machine".

The term "Jenny sandwich" has different meanings in different contexts, ranging from a machine that automatically creates sandwiches to sandwiches made by a gentle, kind, and caring girl.