• Boil the potatoes: Wash, peel, and cube 2 lb potatoes (900 g). Place them in a large pot, cover them with water and bring to a boil. Add ½ teaspoon fine sea salt, lower the heat, cover the pot leaving a small crack open, and cook the potatoes until fork tender, about 15 minutes.

Meat filling:

• While the potatoes are cooking, cook the ground meat.
• Cook meat: Heat 1 tablespoon of oil in the skillet. Add 2 chopped onions and 2 diced carrots and cook on medium heat for about 5 minutes, often stirring, until softer. Add 3 grated garlic cloves, stir for a few seconds, then add 1 lb ground beef (450 g). Cook for 5-6 minutes until the meat is brown, breaking it up with a wooden spoon as you go along.
• Add 1 teaspoon dried parsley, 1 teaspoon thyme, 3 tablespoons tomato paste, 1 teaspoon Dijon mustard, 1 tablespoon Worcestershire sauce, ½ cup broth (125 ml), and some salt and pepper. Stir well to combine.
• Simmer without a lid for about 15 minutes. Add 1 cup of peas (150 g), stir to combine, and cook for another 5 minutes. Adjust the taste with salt and pepper.
• In the meantime, preheat the oven to 350°F/ 180°C.

Mashed potato topping:

• Drain potatoes: Once the potatoes are tender, drain them well and return them to the hot pot. Let them steam for about 1 minute.
• Heat ½ cup milk (125 ml) in a small pan or microwave.
• Mash potatoes: Add milk, 2 tablespoons butter, a few gratings of nutmeg, salt, and pepper. Mash the potatoes with a potato masher until smooth. Stir in the ½ cup grated Parmesan (60 g) and adjust the taste with salt and pepper.

Assemble and bake:

• Spread the mashed potatoes on top of the meat in an even layer. Then, carefully (the skillet is hot and heavy), place the shepherd’s pie onto the middle rack in the preheated oven (Note 4).
• Bake for 25-30 minutes until the filling is bubbling and the topping is golden.
• Let the pie rest for 10 minutes, sprinkle with fresh parsley, and serve.