2 Tablespoons unsalted butter
2 Tablespoons cooking oil
2 cups (12 ounces) Yukon gold potatoes, cut into ¼-inch cubes
1 medium onion, finely chopped
2 cups (12 ounces) roast beef, cut into ¼-inch cubes
2 cloves garlic, minced
¼ teaspoon dried thyme
Salt and freshly ground pepper to taste
½ cup heavy cream
4 fried eggs, if desired
Chopped parsley or chives for garnish, if desired

In a 12-inch skillet, heat butter and oil over medium-high heat. Add potatoes and cook, stirring occasionally, until lightly browned, 810 minutes.  Add onions and cook, stirring occasionally, until soft, about 10 minutes.

Add beef, garlic, thyme; cook, stirring occasionally, until beef browns, about 5 minutes. Season with salt and pepper to taste.

Add heavy cream, stir to combine, and press hash down into the skillet with a metal spatula.  Turn hash in parts every 2 minutes, loosening any browned bits, until the cream has reduced and hash forms a crust, about 10 minutes.  Garnish with parsley or chives and serve hot with fried or poached eggs, if you like.  Yield:  4 Servings.