It takes forever... and ever... and ever.... to make this amazing ... thing. I say "thing", because it's not really a dish on it's own, but it can be a secret ingredients to so many things. It's like roasted garlic, but with a lot more work. I almost always use sweet Onion, here in GA, I would use Vadalia onions. I cut them thinly, but not too thin, and sautee with ample amount of oil (maybe about 1/8 of a cup... or more) for about 45 minutes. I do it on low heat the entire time. One will have to be really patient to do this the right way. for about 20 minutes, it will look like it's not changing at all, but it will come... when 45 min to an hour is over, you will end up with these amber, rich, goodness.
Top pizzas with it, fill frittata with it, make caramelized onion galette with it, have it as a base to your beef stew, have it in savory crepe with brie and pear, put it on polenta.. there's countless of use for these jewel.
This is the end product. If you are going apply much more heat to this in the next cooking step... like put this on pizza and bake it some more, I would not wait until onions are this deep in its amber color.
note: Onion is good for your health! it's been around for a long long time, and many cultures believe in it's healing power!