Shepherd's pie with beef and lamb

Ingredients:

• 900 g potatoes, peeled and cut into 4 pieces
• 2 tablespoons extra-virgin olive oil
• 2 leeks (white and light green parts only), halved lengthwise and cut into 1cm thick slices, rinsed thoroughly
• 350 g of ground beef
• 350 g of ground lamb
• 2 large carrots, diced
• 2 cloves garlic, finely chopped
• 1 tbsp Worcestershire sauce
• 1 tbsp chopped fresh thyme
• 3 tablespoons tomato paste
• 3/4 cup Irish stout (such as Guinness)
• 1 and 1/4 cups lightly salted beef broth
• 1 cup frozen green peas
• 60 g unsalted butter
• 2/3 cup low-fat cream (10%)
• 1 cup grated cheddar (about 110 g)

Preparation:

1. Preheat oven to 200°C.
2. Place the potatoes in a large saucepan, cover with cold water to a depth of 2.5 cm, and season with salt. Bring to a boil, then reduce heat and simmer until tender, 20-25 minutes.
3. Meanwhile, heat the olive oil in a large skillet over medium heat. Add the leeks and sprinkle with 1/2 teaspoon of salt. Cook, stirring, until the leeks are softened but not browned, about 8 minutes. Transfer half the leeks to a large bowl and set aside.
4. Add the ground meat to the skillet with the remaining leeks. Cook over medium heat, breaking up the meat, until no pink remains, about 6 minutes. Drain any excess fat from the pan and season the meat with salt and pepper.
5. Add the carrots, garlic, Worcestershire sauce, and thyme to the ground meat. Make a small hole in the center of the pan and add the tomato paste. Cook the tomato paste, stirring, until slightly darkened, about 1 minute, then add it to the meat mixture.
6. Pour in the stout and simmer until the liquid has evaporated slightly, about 2 minutes. Add the broth and bring to a boil.
7. Cook, stirring, until the carrots are almost tender, about 5 minutes. Add the green peas, reduce the heat to low, and bring to a simmer while you mash the potatoes.
8. Drain the potatoes and let them cool slightly. Transfer them to a bowl with the leeks, add the butter, cream, and 0.5 teaspoon of salt, and mash thoroughly. Stir in 0.5 cup of cheddar.
9. Place the meat mixture in a 3-quart (3-quart) baking dish. Top with the mashed potatoes and spread with the back of a spoon. Sprinkle with the remaining 1/2 cup of cheddar. Bake until bubbly around the edges and the top is golden brown in spots, about 25 minutes.
10. Let rest for 10 minutes before serving.
11. You can make the shepherd's pie up to 2 hours ahead, cover it, and refrigerate it. In this case, bake it for 10 minutes longer.