Rosti-topped lamb & rosemary pie

Active: 30 minutes; Total: 5 hours; Yield: 4 to 6

Lamb leg or shoulder; cut into large chunks	750 grams
Salt
Pepper, freshly ground
Flour, all-purpose	2 tablespoons
Oil, olive	1 tablespoon + 1 tablespoon
Onion; chopped	1 large
Carrot; chopped	1 large
Garlic; crushed	5 cloves
Rosemary; needles picked, finely chopped, plus a few small sprigs	2 sprigs +
Tomato paste	1 tablespoon
Wine, red	200 milliters
Stock, beef	500 milliters
Vinegar, strawberry balsamic	1 tablespoon
Potatoes, floury; cut into chunks	850 grams
Cheddar, sharp; grated	100 grams
Butter, unsalted; melted	25 grams + 25 grams

1. In a large bowl, season the lamb with salt and pepper, then toss with flour. 
2. Heat 1-tablespoon oil in a Dutch oven over high heat, and brown half the lamb on all sides; transfer to a plate, and repeat with the remaining lamb; set aside. 
3. Reduce heat to medium, add 1-tablespoon oil, then the onions and carrot; cook for 10 minutes, stirring occasionally, until soft and golden. 
4. Add the garlic, chopped rosemary, and tomato paste; stir for 1 to 2 minutes. 
5. Return the lamb to the pan, pour in the wine and stock, stir in the vinegar, and bring to a simmer. 
6. Reduce the heat to low, cover, and cook for 3 hours, or until the lamb is tender. 
7. Place the potatoes in a large pot, cover with water, bring to a boil, and cook for 10 minutes, until softened slightly but still holding their shape. 
8. Preheat oven to 375°F.
9. Drain, leaving to cool enough to handle, then grate using the coarse side of the grater. 
10. Place in a medium bowl with the cheddar, 25-grams butter, salt, and pepper; mix until well combined. 
11. Transfer the lamb stew to a 12-inch-by-8-inch baking dish. 
12. Scatter the potato topping over the meat, and poke a few small rosemary sprigs into it. 
13. Brush with the remaining butter, and bake for 35 to 40 minutes, until the topping is golden brown and the stew is bubbling at the edges.

Recipe mildly adapted from Good Food by Cassie Best.