Hamburger Pie with Mashed Potato Topping

Ingredients

• 2 lb russet potatoes, peeled and cubed
• 6 tbsp unsalted butter
• 3/4 cup warm whole milk
• 1 cup shredded sharp cheddar cheese
• 2 tsp kosher salt
• 1 tsp black pepper
• 1 1/2 lb ground beef, 85 percent lean
• 1 large yellow onion, diced
• 3 cloves garlic, minced
• 2 tbsp all-purpose flour
• 1 cup beef broth
• 1 can tomato sauce, 8 oz
• 1 tbsp Worcestershire sauce
• 1 tsp dried thyme
• 3 cups cut green beans, fresh or frozen
• 1 large egg yolk

Before you cook

• Peel the potatoes and cut them into 1-inch cubes.
• Dice the onion and mince the garlic.
• Warm the milk.
• Grease a 2 1/2-quart baking dish.

Steps

1. Put the potato cubes in a large pot, cover them with cold salted water, and bring them to a boil.
2. Boil the potatoes for 15 minutes, until a fork slides through with no resistance.
3. Drain the potatoes and return them to the hot dry pot for 1 minute so the surface steam evaporates.
4. Mash the potatoes with 4 tablespoons of the butter and the warm milk until smooth.
5. Stir in the cheddar, 1 teaspoon of the salt, half the pepper, and the egg yolk.
6. Heat the oven to 400 degrees Fahrenheit.
7. Melt the remaining 2 tablespoons of butter in a large skillet over medium-high heat.
8. Brown the ground beef for 8 minutes, breaking it into crumbles.
9. Pour off the excess fat.
10. Add the onion and cook for 5 minutes, until soft.
11. Add the garlic and cook for 30 seconds.
12. Sprinkle in the flour and stir for 1 minute.
13. Pour in the beef broth and tomato sauce and stir until the gravy thickens, about 3 minutes.
14. Stir in the Worcestershire, thyme, the remaining salt and pepper, and the green beans.
15. Spread the beef mixture in the greased baking dish.
16. Spoon the mashed potatoes over the top in rough mounds, then drag a fork across them to raise ridges that will brown.
17. Bake uncovered for 25 minutes, until the potato peaks are deeply browned and the filling bubbles at the edges.
18. Let the dish rest for 10 minutes before serving.