Ultimate slow-roasted lamb: 12-hour Lamb Shoulder

5 servings


13 hours 10 minutes

total time


1 ⅗ - 2.2kg / 3.2 - 4.4lb lamb shoulder (, bone-in, Note 1)

2 cups water (Note 2)

1 brown onion (unpeeled, cut into 6 wedges, Note 3)

2 1/2 tsp fresh rosemary (, chopped, finely)

1 tbsp dried oregano

2 garlic cloves (big!) (, finely chopped)

1 tsp salt (, kosher or cooking salt, or 3/4 tsp table salt)

1/2 tsp black pepper

1/4 cup extra virgin olive oil

1 tsp cornflour / cornstarch

1/4 cup water

1/4 tsp salt


Preheat oven to 230°C / 450°F (210°C fan).

Marinade/rub: Mix the Marinade ingredients in a small bowl. Rub all over the lamb surface, getting it right into all the cracks and crevices!

Marinate 2 - 24 hrs: If time permits, marinate for 2 hours on the counter in a roasting pan, or up to 24 hours in the fridge. I skip this step more often than not, however. (Note 4)

Prepare roasting pan: Scatter onion in the base of the roasting pan. Place lamb shoulder on top . Pour water into pan.

Roast uncovered for 45 minutes.

Slow-roast 12 hours: Turn oven down to 100°C/210°F (both fan and standard, Note 5). Cover lamb with baking paper, then a double layer of foil and seal very tightly to avoid water evaporation. Roast for 12 hours (I always do overnight!).

Check meat – Test side of lamb with two forks. The meat should be fall-apart tender. If not, cover and return to oven.

Remove lamb: There will (should!) be a lot of liquid pooled under the lamb in the roasting pan. Remove lamb to a large dish. Cover loosely with foil to keep warm. It will stay warm for 2 to 3 hours. See Note for reheating / making ahead.

Lamb Jus:

Reduce liquid: Strain all the liquid in the roasting pan into a saucepan (Note 2). Bring to a boil then simmer rapidly on medium-high until it reduces down to 1 cup (250ml).

Thicken: Mix cornflour with water. Pour into jus in a thin stream while stirring continuously. Continue to cook for a minute or two over medium heat, stirring every now and then, until it thickens to a syrup consistency. Add salt and pepper to taste.


Serve Slow Roasted Lamb with Jus. Use tongs for tearing meat off - no knife for carving needed! Pictured in post with Greek Lemon Roasted Potatoes, a perfect match for this Greek-ish flavoured lamb. Roasted Vegetables would also be ideal.


Serving Size



377 kcal

Total Fat

21 g

Saturated Fat

5 g

Unsaturated Fat

14 g

Trans Fat



129 mg


727 mg

Total Carbohydrate

4 g

Dietary Fiber

1 g

Total Sugars

1 g


41 g

5 servings


13 hours 10 minutes

total time
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