Classic Shepherd's Pie with Cheddar Mash

Peel and quarter 2 lb Yukon Gold potatoes. Cover with cold salted water in a large pot, bring to a boil, and simmer 15-18 minutes until fork-tender.

Meanwhile, heat 1 tbsp olive oil in a large skillet over medium-high heat. Add ground lamb, breaking it up, and brown 6-8 minutes until deeply caramelized. Drain excess fat, leaving about 1 tbsp.

Reduce heat to medium and add onion and carrot. Sweat 5 minutes until softened, then add garlic and tomato paste, cooking 1 minute until fragrant.

Sprinkle flour over the mixture, stir, then deglaze with 1 cup beef stock, scraping the pan. Add Worcestershire, thyme, and rosemary.

Simmer 8-10 minutes until the sauce is thick enough to coat a spoon. Stir in frozen peas, season with salt and pepper, then transfer to a 9x13 baking dish.

Drain potatoes and return to the hot pot for 1 minute to evaporate moisture. Mash with 4 tbsp butter, ½ cup warm milk, and 1 cup grated cheddar until smooth and fluffy. Season with salt.

Preheat oven to 400°F (200°C). Dollop mash over the filling, then spread and rough up the surface with a fork to create peaks that will crisp up.

Bake 25-30 minutes until the top is golden brown and the filling bubbles at the edges. Rest 10 minutes before serving.