Jigo Ghearch (جیگو قارچ) — Persian-Style Mushroom Lamb Roast

• 2400 gBone-in leg of lamb (trim excess surface fat to a thin layer; pat very dry)
• 24 gGarlic (finely grated or crushed (about 8 cloves))
• 18 gFine sea salt (divided)
• 4 gBlack pepper (freshly ground (about 2 teaspoons), divided)
• 60 gUnsalted butter (divided)
• 1000 mlWater (plus more if needed to keep a shallow braise)
• 450 gButton mushrooms (wiped clean and thickly sliced)
• 90 gTomato paste (about 6 tablespoons)
• 300 gGreen beans (trimmed and cut into 3 cm pieces)
• 250 gCarrots (peeled and cut into 2 cm chunks)
• 600 gYukon Gold potatoes (peeled and cut into 4 cm chunks)

Instructions

1. 1

   Heat the oven to 160°C / 325°F with a rack in the lower third. Pat the lamb completely dry. Rub all over with the grated garlic, 12 g of the salt, and 3 g of the black pepper. Let it sit at room temperature for 30 minutes to take the chill off for more even braising.

2. 2

   Place a large Dutch oven over medium-high heat for 3 minutes. Add 30 g butter and let it foam. Sear the lamb 4–5 minutes per side (including the thick ends), turning carefully, until deeply browned. This browning builds the base flavor for the braising liquid and final reduction.

3. 3

   Pour in 1000 ml water, scraping the bottom for 1 minute to dissolve browned bits. Bring to a gentle simmer, then cover tightly and transfer to the oven. Braise for 2 hours, turning the lamb once at the 1-hour mark, keeping the liquid at a steady, quiet simmer.

4. 4

   After 2 hours, remove the pot from the oven. Add the carrots and potatoes around the lamb, then scatter in the green beans. Cover and return to the oven for 60 minutes, or until the lamb is very tender and the vegetables are cooked through but not falling apart.

5. 5

   Carefully transfer the lamb to a warm platter and tent loosely with foil. Using a slotted spoon, move the vegetables to a serving dish and cover. Skim excess fat from the surface of the braising liquid. You should have about 600–800 ml liquid; add 100–200 ml water if it looks too low.

6. 6

   Set the Dutch oven on the stovetop over medium-high heat. Add the remaining 30 g butter, then add the sliced mushrooms. Cook 8–10 minutes, stirring often, until the mushrooms release their liquid and begin to brown. This concentrates umami and prevents the sauce from tasting watery.

7. 7

   Add the tomato paste and cook 2–3 minutes, stirring constantly, until it darkens slightly and smells sweet rather than raw. Simmer the pot uncovered for 12–18 minutes, stirring every 2 minutes, until the sauce reduces to a glossy consistency that coats a spoon.

8. 8

   Season the reduction with the remaining 6 g salt and 1 g black pepper, adjusting to taste. Slice or pull the lamb into thick portions. Spoon the mushroom–tomato reduction over the lamb and serve with the braised vegetables on the side, using extra sauce as a gravy.