Ensure corned beef is cooked and shredded or finely diced. Dice the cooked potatoes, yellow onion, and red bell pepper into approximately 1/2-inch pieces.

Heat the olive oil and unsalted butter in a large cast-iron skillet (or heavy-bottomed pan) over medium heat.

Add the diced onion and red bell pepper. Sauté for 5-7 minutes, until softened and translucent.

Add the diced cooked potatoes and shredded corned beef to the skillet. Gently mix with the onions and peppers.

Sprinkle with Worcestershire sauce, smoked paprika, salt, and black pepper. Stir well to combine. Flatten the hash mixture slightly with your spatula into an even layer across the bottom of the skillet.

Let the hash cook undisturbed for 8-10 minutes, allowing a crispy crust to form on the bottom. Avoid stirring too frequently.

Using a spatula, carefully flip sections of the hash to expose the browned side. Press down lightly to compact the hash again. Continue cooking for another 8-10 minutes, or until the second side is golden brown and crispy. If desired, you can break up larger potato pieces with a potato masher or fork for a more traditional texture, then re-flatten and crisp.

While the hash is crisping, if serving with eggs, prepare them. For poached eggs: bring a pot of water with 1 tbsp vinegar to a gentle simmer. Carefully crack each egg into a small bowl, then gently slide into the simmering water. Cook for 3-4 minutes for runny yolks. Remove with a slotted spoon.

Once the hash is deeply golden and crispy, remove from heat. Garnish generously with fresh chopped parsley. Serve hot, topped with poached eggs if desired.