Roast Beef Hash

Ingredients

• 3 tbsp unsalted butter
• 1 tbsp vegetable oil
• 1 large yellow onion, chopped
• 1 lb boiling potatoes, peeled and cut into 1/2-inch dice (about 3 cups)
• 1 lb cooked roast beef, chopped into 1/2-inch pieces
• 1/2 cup leftover beef gravy or beef stock
• 1 tbsp Worcestershire sauce
• 1 tsp coarsely ground black pepper
• 3/4 tsp kosher salt
• 2 tbsp chopped fresh parsley

Before you cook

• Peel the potatoes and cut them into half-inch dice.
• Put the diced potatoes in a saucepan, cover with cold salted water and bring to a boil.
• Boil 6 minutes, until a knife tip meets slight resistance in the center, then drain them and spread them on a plate to steam dry.
• Chop the onion.
• Chop the roast beef by hand into half-inch pieces; a food processor turns it to paste.
• Chop the parsley.

Steps

1. Melt 2 tablespoons of the butter with the oil in a 12-inch cast-iron skillet over medium-high heat.
2. Add the onion and cook 4 minutes, stirring, until the edges brown.
3. Add the parboiled potatoes in a single layer and season with the salt and pepper.
4. Cook 8 minutes, turning the potatoes only two or three times, until they are browned on several sides.
5. Add the chopped roast beef and stir once to combine.
6. Pour the gravy and Worcestershire sauce over everything.
7. Press the hash down firmly into an even cake with the back of a spatula.
8. Reduce the heat to medium and cook undisturbed for 7 minutes, until the underside is dark and crusty.
9. Flip the hash in sections and press it down again.
10. Cook 6 minutes more, until the second side has crusted and the liquid has cooked away.
11. Dot the remaining tablespoon of butter over the top and let it melt in.
12. Scatter the parsley over and serve from the skillet.