I have heard of at least 5 different ways of preparing this deliciously caloric meal, and I will now document what I feel is the best of them.
How to make Corned Beef Hash:
Get a frying pan going to melt the butter and heat the oil (just use enough to fry in). Add to it the hash browns (season them up with the salt, pepper, and onion powder). Wait till they're nice and golden brown. Remember to stir. Once that is nice and heated, you want to chop the lump of corned beef into nice small pieces, and add that to the pan. Also, throw in the peas (without the juice). Toss it around for a minute or two, and serve it up with plenty of ketchup. This makes enough to feed atleast 3 people.
Enjoy. I should probably warn you that unless you have some sort of death wish, it is not recommended that you ever actually prepare or eat this.
You are probably thinking that you could no doubt improve on this tasty treat by preparing it with fresh peas, a real onion, and maybe even real potatoes. All I have to say is that I wouldn't do that if I were you. Really, I wouldn't. You won't like it.