Classic Shepherd's Pie with Rosemary Mashed Potatoes

Peel and quarter 2.5 lb Yukon gold potatoes, place in a large pot, cover with cold salted water and bring to a boil. Cook 15-18 minutes until fork-tender.

Meanwhile, heat 1 tbsp olive oil in a large ovenproof skillet over medium-high heat. Add 1.5 lb ground lamb and brown for 6-7 minutes, breaking it up, until deeply caramelized. Drain excess fat, leaving about 1 tbsp in the pan.

Add 1 diced onion and 2 diced carrots and sweat for 5 minutes until softened and translucent.

Stir in 3 minced garlic cloves, 2 tbsp tomato paste and 1 tbsp chopped fresh rosemary. Cook 90 seconds until fragrant and the paste darkens.

Sprinkle 2 tbsp flour over the meat and stir for 1 minute to cook out the raw taste.

Deglaze with 1/2 cup dry red wine, scraping the fond, then add 1.5 cups beef stock, 1 tbsp Worcestershire sauce and 1 tsp fresh thyme leaves. Simmer 8-10 minutes until the sauce is thick enough to coat a spoon.

Stir in 1 cup frozen peas, taste and season with salt and pepper, then remove from heat. Preheat oven to 400°F (200°C).

Drain the potatoes and return to the hot pot for 30 seconds to evaporate moisture. Mash with 6 tbsp butter, 1/2 cup warm whole milk, 1/4 cup grated parmesan, salt and pepper until silky.

Spread the mash evenly over the lamb filling, then drag a fork across the surface to create ridges: these will crisp beautifully in the oven.

Bake for 25-30 minutes until the filling bubbles vigorously at the edges and the potato peaks are burnished golden brown.

Rest 10 minutes before scooping so the layers hold their shape.