Sour and bitter can be good though. I love fresh onion as is. I ghetto caramelize it a bit to make it more palatable to my girlfriend though. For that you don't need to do a proper caramelization, getting the process going and adding a bit of sugar is enough.
I love to add vinegar too though. Vinegar, a bit of sugar, a bit of salt, some time on the pan, delish.
You don’t need to stick to stupid things such as labels at home. Do whatever you want. On the web, though… you’ll have the swift justice of the FOOD PURISTS VIGILANTES! (We’re still workshopping that name.)
I know you're joking, but the only way I can see it taking that long is if you put whole onions into an oven set to 180° to 200° F.
In a frying pan, one can easily caramelize an entire large frying pan of onions in about 30 minutes, or even faster if you decide to use physics to your advantage, and add a small amount of water to your pan and caramelize your pan of onions within 14 minutes. This is an advanced technique that requires some experience to try to use. Much like making a Dark Roux in 15 minutes.
I'm absolutely not joking. If you're cooking it for less than 45 minutes, you're not caramelizing the onions. Frequent stirring, adding water, whatever, you can get the color and texture of caramelization, but not the flavor.
I spent a couple of years making slightly disappointing meals because I was focused on the color and texture of my onions instead of the flavor. When I finally took the time to fully caramelize them again, I remembered what I had been missing.
Try it and taste the difference if you don't believe me.
I know it's not exactly the same as a low temp for a while. But you can get pretty good results with a high temp, just need to deglaze more frequently, usually with water until they're almost done. Then wine and/or balsamic is good.