I call it Shepherd's pie, but technically because I used beef and not lamb, I'm supposed to call it Cottage Pie. Whatever. It's good.
I modified this slightly from an America's Test Kitchen recipe. The original recipe was for diced lamb shoulder chops. I'm sure that'd be delish, but I was too lazy. Can be assembled in either a 9x13 pan or a 10 inch pie plate. Serves 6-8.
1 lb ground lamb (or in my case, ground beef)
1 1/2 tsp salt
1 tsp ground black pepper
3 Tbsp vegetable oil, if you need it
1 medium onion, chopped coarse
2 medium carrots, cut into 1/4 inch slices
1 medium clove garlic, minced
2 Tbsp flour
1 Tbsp tomato paste
2 cups chicken broth
1/4 cup full-bodied red wine (I didn't have this, but I did have some white wine so I used that instead and it was still good)
1 tsp Worcestershire sauce
1 tsp chopped fresh thyme leaves
1 tsp chopped fresh rosemary
1 cup frozen peas, thawed
2 lbs large russet potatoes, peeled and cut into 2 inch cubes
1 tsp salt
6 Tbsp butter
3/4 cup whole milk, warmed
2 large egg yolks
ground black pepper
FOR THE FILLING: Season the meat with salt and pepper. Heat oil (if needed, I never use it) in a large skillet over medium high heat until shimmering. Add meat, onions, and carrots and cook, stirring occasionally, until meat is well browned, about 5 minutes. Reduce heat to medium and add garlic, flour, and tomato paste and cook until garlic is fragrant, about 1 minute. Whisk in the stock, wine, and Worcestershire sauce. Stir in the thyme and rosemary. Bring to a boil, reduce heat to low, cover, and simmer for about 15 minutes.
FOR THE TOPPING: Meanwhile, put the potatoes into a large saucepan; add water to cover and 1/2 tsp salt. Bring to a boil and continue to cook over medium heat until the potatoes are tender when pierced with a knife, 15 to 20 minutes. Drain the potatoes well and return them to the pan set over low heat. Mash potatoes, adding butter as you mash. Stir in the warm milk and then the egg yolks. Season with the remaining 1/2 tsp salt and pepper to taste. (I thought it needed even more salt than this.)
TO ASSEMBLE AND BAKE: Adjust oven rack to the middle position and heat the oven to 400 degrees. Stir the peas into the meat mixture and check the seasonings. Pour the meat mixture evenly into a 9x13 baking dish. With a large spoon, place the mashed potatoes over the entire filling. Starting at the sides to ensure a tight seal, use a rubber spatula to smooth out the potatoes and anchor them to the sides of the baking dish. (You should not see any filling.) Bake until the top turns golden brown, 20 to 25 minutes. Let rest for 5 to 10 minutes and serve.
Pie plate assembly: The filling and potato topping fit nicely in a standard 9x13 baking dish, but for a fancier presentation bake the pie in a 10 inch pie plate. The mashed potato topping rises high above the filling, much like a lemon meringue pie. To do this, place the filling in a 10 inch pie plate and then drop spoonfuls of mashed potatoes around the perimeter of the pie plate. Use a rubber spatula to attach the potatoes to the rim of the pie plate. It's important to seal the edges this way to prevent the filling from bubbling out of the pie plate in the oven. Drop the remaining mashed potatoes in the center of the pie plate and then smooth the top with a spatula. Because the topping rises so high, bake the pie on a rimmed baking sheet to catch any leaks. (You might even want to do that with the 9x13 version - I guess my seals weren't perfect so I got a good bit of dripping in my oven.)