My new fool proof, easy way of doing corned beef was an idea I got from All You Can Eat channel and modified it. I microve wave the pre-made corned beef hash in a bowl (I add some garlic pwder &onion powder and a dash of oil) for 2 mins or so to heat through. Then I pour the hash into a greased pie tin and put it under the broiler in my oven for 20 to 30 secs or until crispy(you could use a toaster oven, also). Perfect hash every time and no fear of burning or trying to turn in pan with everything sticking to the bottom of the pan!
Looks as good as corned beef and hash can get. However, the garlic would not have been the first thing that I added to the hot oil.... IMO, doing that just increases the chance of the garlic burning and ruining the dish before it's edible. "Browning" garlic is not necessary. Personally, I would start with the onions and then after they sauteed follow up with either "garlic then hash" or "hash then garlic".
Be sure to use a cast iron skillet and a lot of oil. If you don't have one, use one of those nonstick frying pans because this stuff sticks like glue. By the way, corned beef hash is delicious when you mix it with cooked rice. Try it.
Heat the iron skillet with some oil for about 3 to 5 minutes before adding any food to your pan. The food will not stick at all to your pan. Thats what i was taught im using one now 😉.