Start by adding the butter to a large 12” to 14” cast-iron skillet over medium-low heat. Allow it to melt completely before adding the onions. Sauté the onions gently, allowing them to caramelize, which takes about 10 minutes. You’ll notice the lovely aroma filling your kitchen as they turn golden brown.
Next, add in the garlic and sauté for 30 to 45 seconds or just until fragrant. Be careful not to let it burn, as burnt garlic can turn bitter. Stir well to combine the flavors.
Now it’s time to incorporate the corned beef and potatoes. Add them to the skillet and pan roast over medium heat. Cook for about 12 to 15 minutes, stirring every 1 to 2 minutes. You’re aiming for the potatoes to become browned and tender. Pay attention to their color; they should be a nice golden brown.
Once the potatoes are cooked through, finish the dish by seasoning with salt, pepper, chives, parsley, and rosemary. Keep everything warm while you prepare your eggs. This will ensure that the flavors meld beautifully.
Serve with your desired type of cooked eggs. Whether you like them fried, scrambled, or poached, they make the perfect accompaniment to your Corned Beef Hash.