I was always taught to fry chopped onions and only after that was done, put in the minced meat. Why does that make any sense? You just risk burning the onions like that.
I started doing it the other way around (meat first, then onions/garlic) after I moved for myself.
Is one better than the other, and why?
Onions take up the flavors of the spices in the oil, and if you want to caramelize them you need the direct heat. It's impossible to burn them this way unless you burn everything else as well because once you put the meat in the heat becomes more broadly distributed.
Burnt onions are delicious anyway.
Onions won't caramelize if you add them to the meat instead of cooking them first. If you cook the meat first, and add the onions after, you're not really sauteing them, you're steaming them till soft. It doesn't create optimum flavor. Unless you are impatient and are cooking your onions on high heat, they won't burn.
That said, garlic is a very different story. Garlic is easy to burn, which creates a bitter flavor.
So, cook your onions first, until they caramelize, then add the meat and garlic, and cook till the meat has browned.
Nope. As a matter of fact, it would be even better to cook the onions first, because the meat isn't going to render much fat anyway, and you'd want the onions to add flavor to the meat as it cooks.
I have to eat lean red meat myself (just had gallbladder surgery a couple weeks ago), and that's still how I do it, no matter how little the fat content is. It's the technique that's important.
by the time you have done this your onions will have been steamed into mush, and your meat will probably be overcooked, too.
you want to maximize the maillard reaction for both the meat and the onions. whichever order you do this in, if you're only using one pan and you don't remove a thing, it's not going to work well. what you should do is brown either the meat or the onions, remove them from the pan, brown the remaining thing, and then mix the first thing back in. I recommend browning the meat first so that you can fry the onions in some of the rendered fat.
also - if you're browning a fuckton of ground beef, don't do it all at once, do it in portions so that you aren't crowding the pan. the maillard reaction is impeded by the presence of water because the evaporation of water consumes too much thermal energy. if you crowd the pan you're just braising the beef in ground-beef-juices and not really frying it. that's not the way to flavortown, anon.
A. the onions need to cook in OIL to soften them and remove the bitterness, if you add them with the meat the meat juices are likely to stew the onion; which is not good.
B. the amount of heating they need is relative to the volume of food in the pan, cook them with meat and it means generally that you overcook the meat; or undercook the onions