This idea might just be the push I need to get a slow cooker. I've been thinking about it for quite a while, but felt no real need for one, but the thought of French onion soup is starting to create that need.
It may also create the need for a storage cabinet too, but I think that is going to be inevitable eventually anyway.
Buy a small 1 1/2 qt. size crock pot. Just right for a single person or a couple.