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slow roast leg of lamb

Slow Roast Leg of Lamb with Rich Gravy

This slow roast leg of lamb is fall-apart tender, infused with rosemary and garlic, and served with a glossy, flavorful gravy. Perfect for holiday feasts or cozy family dinners, the long, gentle roasting ensures juicy meat and a golden crust every time.
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Prep Time 20 minutes
Cook Time 5 hours 30 minutes
Total Time 5 hours 50 minutes
Servings: 8 servings
Course: Dinner, Main Course
Cuisine: British, Mediterranean
Calories: 574
Ingredients Method Notes

Ingredients
  

For the Lamb Roast
  • 2.25 kg bone-in leg of lamb or lamb shoulder for richer flavor
  • sea salt and freshly ground black pepper to taste
  • 1.5 tbsp extra virgin olive oil
  • 1 head garlic unpeeled, sliced in half horizontally
  • 1 large onion quartered, skin on
  • 2 sprigs fresh rosemary use 4 sprigs for bolder flavor
  • 3 cups low-sodium beef stock or homemade for maximum flavor
  • 2 cups water
For the Gravy
  • 4 tbsp all-purpose flour
  • 1 cup water adjust for desired thickness
  • sea salt and freshly cracked black pepper to taste

Method
 

  1. Preheat oven to 170°C / 335°F (150°C / 300°F fan). In a large roasting pan, arrange garlic halves, onion quarters, and rosemary sprigs as a bed for the lamb.
  2. Place lamb on top, season generously with salt and pepper on both sides.
  3. Drizzle olive oil over lamb, pour beef stock and water into the pan. Cover tightly with foil.
  4. Roast for 4.5 hours, checking halfway to ensure liquid remains in the pan.
  5. Remove foil, turn lamb over, and roast uncovered for 45 minutes until golden brown.
  6. Transfer lamb to a platter, spoon over some pan juices, cover loosely with foil, and rest for 20–30 minutes.
  7. To make gravy, place roasting pan over medium-high heat, skim excess fat, whisk in flour, and cook into a paste.
  8. Gradually add ½–1 cup water, whisking until smooth. Season to taste, strain into a jug, and serve.

Notes

For extra richness, swap half the gravy water for extra stock or a splash of red wine. Use lamb shoulder for a fattier, more flavorful roast. To keep lamb warm for up to 1.5 hours, leave covered in foil in a low oven at 70°C / 160°F.