If using the eggs, preheat oven to 400˚F.
Heat olive oil and butter in a large skillet, preferably cast iron skillet.
To the heated butter and oil, add onions and cook for 2 minutes. Stir occasionally.
Stir in garlic and cook for 15 seconds.
Add potatoes, season with salt, pepper, oregano, and basil; cook over medium-high heat for 15 minutes, or until slightly browned and tender. Stir occasionally.
Stir in corned beef and worcestershire sauce; cook for 5 more minutes, or until crispy.
Remove from heat.
If using eggs, continue with the recipe. If not, you can garnish with parsley, and serve.
If using the eggs, make 4 to 6 wells in the hash.
Crack an egg into each well.
Season the eggs with salt and pepper.
Bake hash in the oven for about 8 to 10 minutes, or until the egg whites are set.
Remove from oven.
Garnish with parsley.
Serve.