I used to think I knew how to caramelize onions, until I found out that, technically, there's no such thing. Of course I don't expect other recipe writers, chefs and cooking instructors to stop using the term -- that horse left the barn too long ago -- but I like precision, so I now talk about slow-browned onions (on the left in the photo) and quick-browned onions (on the right). I use the quick browned version in my patty melt and the slow browned ones in red pepper and onion soup. Both of them go into French onion soup. Either way you cook them, they're a great ingredient to have on hand.
Image © Dave Scantland