Tandoori Leg of Lamb

Using a sharp, narrow boning knife, make deep slashes all over the leg — 6 to 8 cuts per side, each about 3–4 cm deep and angled to reach as close to the bone as possible. Work methodically: score the top, the underside, and the shank end. The goal is to create as much marinade-to-meat contact as possible and to reduce the effective thickness of the leg for more even cooking. Score through any thick fat cap as well.

Mix the lemon juice, half the Kashmiri chilli powder, and the salt into a rough paste. Rub this first marinade aggressively all over the lamb — over the surface, and deep into every slash and score with your fingers. This acid-and-salt first marinade begins breaking down the surface proteins and carrying heat deep into the meat. Rest for 30 minutes at room temperature while you prepare the second marinade.

Whisk together the yogurt, oil, remaining Kashmiri chilli, cumin, coriander, garam masala, turmeric, ginger paste, and garlic paste until smooth and uniformly orange-red. Taste it — it should be bold, fragrant, and slightly salty (the lamb already carries salt from the first marinade). Apply this second marinade all over the lamb, working it deep into every cut and under any loose membrane. Place in a large dish, cover with plastic wrap, and refrigerate for 4–6 hours, or ideally overnight.

Bring the lamb to room temperature 2 hours before cooking. Preheat the oven to 220°C (425°F) with a rack in the upper third. Place the lamb on a wire rack set over a roasting tray (to catch drips and allow air circulation under the meat). Roast at 220°C for 25–30 minutes until the marinade coating is charred and blackened in spots — this char is essential flavour. Meanwhile, heat the ghee in a small pan. After 25 minutes, baste the lamb generously with ghee, then reduce the oven to 180°C (350°F) and continue roasting for 45–60 minutes more (about 20 min per 500g for medium-pink).

Transfer the lamb to a cutting board and tent loosely with foil — do not wrap tightly, which traps steam and softens the crust. Rest for 20 minutes minimum. This is not optional: the internal temperature will rise 2–3°C more (carry-over cooking) and the muscle fibres will relax and reabsorb the juices. A leg cut too soon bleeds on the board and the meat is tough. Use the resting time to scrape the roasting tray drippings into a small pot and reduce with a splash of water for a pan sauce.