Creating your Shepherd’s Pie can be made simple by following these steps:

1. Preheat Oven: Begin by preheating your oven to 400°F (200°C).

2. Cook the Meat: In a large skillet, cook the ground lamb or beef over medium heat until browned. Drain excess fat if necessary.

3. Sauté Vegetables: Add the diced onion, carrots, and garlic to the skillet. Sauté for about 5 minutes until the onion is translucent.

4. Season: Stir in the tomato paste, Worcestershire sauce, thyme, salt, and pepper, mixing well to incorporate.

5. Add Broth: Pour in the broth and bring the mixture to a simmer. Cook for about 10 minutes until slightly thickened. Add frozen peas and mix well.

6. Prepare Potatoes: Meanwhile, boil the peeled and cubed potatoes in salted water until tender (about 15 minutes).

7. Mash Potatoes: Drain the potatoes and return to the pot. Add milk and butter, mashing until smooth and creamy.

8. Assemble Pie: Pour the meat mixture into a baking dish, then spread the mashed potatoes over the top, using a fork to create peaks.

9. Add Cheese: If desired, sprinkle shredded cheddar cheese over the mashed potatoes for added flavor.

10. Bake: Place in the preheated oven and bake for 25-30 minutes until golden and bubbly.