For the lamb:
Marinate the lamb with the herbs (coriander stalks only) and vegetables for at least 2 hours. Sear, ensuring the meat is cooked all over, and place in an oven tray. Add the vegetables and water and cook in the oven for 4 hours at 160oC. Check after 2 hours (and every half hour after that), adding more water if required. When it's ready, the lamb should be falling off the bone. Remove from the oven, splash 200 ml pisco all over it, cover with foil and allow to rest. When the meat is cold, shred it, discarding any fat and sinew. Place into a tray, cover with cling film and weigh the meat down with a block. After it's been pressed for 2 hours, cut it into rectangular pieces.
For the quinoa:
Bring the quinoa to the boil in 3 times its quantity of water. Simmer for 15 mins or until it 'pops'. Strain, season with salt, add a drizzle of olive oil and put to one side.
For the grapes:
Blanch the grapes for 6 mins, strain and drizzle with the remaining pisco. Put to one side.
For the coriander puree:
Blend the coriander leaves with 100 ml olive oil until it forms a paste. Put into a container ready to use.
To serve:
Sear the pieces of lamb in very little oil until they are golden brown. Drizzle with the lamb jus and coriander puree. Serve with the warm black quinoa topped with the grapes. Garnish with mixed cress.