Dice the onion and cube the potatoes.

Heat the vegetable oil in a large frying pan or cast-iron skillet over medium-high heat.

Add the diced potatoes and onions to the hot skillet. Cook for about 5 minutes, stirring occasionally, until they begin to brown.

Add the canned corned beef to the skillet. Break it apart with a wooden spoon as it cooks.

Pour in the apple cider vinegar and let it cook off slightly for 2-3 minutes.

Reduce the heat to medium, cover the skillet, and cook for an additional 15 minutes, or until the potatoes are tender.

If you prefer a crispy hash, remove the cover during the last few minutes of cooking and allow the bottom to crisp up. You can flip it once to crisp the other side.

Season the corned beef hash to taste with salt and black pepper. Garnish with fresh parsley if desired before serving.