Agnello alle Erbe di Montagna Abruzzese — Cook

Ingredients

1 (approx. 2 kg) bone-in leg of mountain lamb, Apennine-grazed; lowland lamb lacks the required flavour complexity
For the herb paste
15 g fresh wild thyme, leaves stripped; cultivated acceptable, less complex
15 g fresh wild marjoram, leaves stripped
10 g fresh rosemary, needles only, woody stems discarded
6 garlic cloves, peeled
8 juniper berries, lightly crushed
80 ml extra-virgin olive oil, Abruzzese if available
For the roasting bed
800 g floury potatoes, quartered, unpeeled
2 (approx. 300 g) white onions, quartered

Method

1
Twenty-four hours before roasting, combine the thyme, marjoram, rosemary, garlic, and juniper berries in a mortar. Pound to a rough, coarse paste — not smooth. Work in the olive oil to bind. The paste should smell sharply of juniper and raw garlic at this stage; that sharpness will temper overnight.
2
Pat the leg dry. Spread the herb paste over the entire exterior surface, pressing it into any natural seams in the meat. Cover loosely and refrigerate for 24 hours. The paste must penetrate the surface and the garlic must lose its raw harshness before the lamb enters the oven — this is where the dish lives or dies; a paste applied moments before roasting produces a flat crust with no depth.
3
Remove the lamb from the refrigerator one hour before roasting to allow it to come toward room temperature. Heat the oven to 180 °C. Arrange the quartered potatoes and onions in a single layer across the base of a heavy roasting pan to form the bed.
4
Set the lamb directly on top of the potato and onion bed. Roast at 180 °C, calculating 20 minutes per 500 g of the leg's weight. For a 2 kg leg this is 80 minutes. After the first 30 minutes, the herb crust should be caramelising and fragrant — a deep, resinous aroma of juniper and browned rosemary rising from the oven is the signature indicator that the crust is forming correctly.
5
At the calculated time, pierce the thickest part of the leg away from the bone. The juices should run with only a trace of rose; the internal flesh should resist with a gentle firmness under finger pressure rather than feeling soft and yielding. The potatoes and onions beneath will be lacquered in herb-infused lamb fat.
6
Remove the lamb from the oven. Cover the pan tightly with foil and rest for 20 minutes without cutting. Carryover cooking continues and the juices redistribute through the meat. Carved too early, the juices are lost immediately to the board.
7
Carve at the table. Serve the potato and onion bed alongside; taste before seasoning — the lamb fat and herb oil will have concentrated on the vegetables.