This question stems from an argument that I had with my 94 year old grandmother. She likes to order French onion soup at restaurants, but she doesn't like it to be served with the cheese on top. She swears that onion soup didn't used to come with the cheese on top, and that this is some sort of recent phenomenon. I told her I have never heard of such a thing; I was under the impression that onion soup with cheese on top went back even further than my grandmother does.
What I'm thinking is that she's remembering back to World War II, and that many things were being rationed, possibly including the cheese that was put on top of onion soup. She may have started eating onion soup just when there didn't happen to be any cheese on it, and then never got used to it when it went back to its more traditional form.
With that said: Does anyone know if French onion soup has always been served with cheese on top? Was there ever a time (such as during the war) that onion soup was served without the cheese? Was there a regional preference about whether the soup got cheese on it or not (my grandmother lived in New York State and New York City up until the late 40s)?
P.S. -- I promise if I find out that I'm right that I won't go and tell my grandmother she was wrong. I just want to know for my own benefit.