In a large frying pan, melt the butter on medium heat. Then add in the diced onion. Stir well then place a lid on the pan. Cook for 5 minutes or until translucent but not burnt.
Add the potatoes and corned beef, mix once. Then pour the Worcestershire sauce over the potatoes and corned beef. Mix one last time then let the corned beef and potatoes sizzle and cook for 5 minutes. Half way through using a spatula carefully life up the mixture and see if it has a nice crispy edge. Flip portions of the hash over, pat down with a spatula and cook for an additional 5 minutes.
Before serving seasoning with minced parsley and dill and season with salt and pepper. Divide evenly among plates and enjoy.
Potatoes - 2-½ cups diced potatoes equals about 3 russet potatoes. You can use the leftover cooked potatoes you have on hand or boil the diced potatoes (add double parts water, 1 tablespoon salt and boil for 10-15 minutes until fork tender but not falling apart) before you are ready to fry the corned beef hash.
Corned Beef - If you want more of a canned texture of corned beef you can run your cooked corned beef through a food processor until very tiny in size.
Herbs - If you don't happen to have fresh herbs on hand you can supplement for dried herbs.
Leftovers - If you only have 1 cup of corned beef leftover over then only add 1 cup of diced potatoes (1-2 medium-russets).