1
Preheat the oven to 180ºC/350ºF/Gas Mark 4.
2
Bash the spices in a pestle and mortar along with the garlic and salt. Stir the oil into this and then coat the lamb in these spices on a large, deep roasting tray. Cover with tin foil and place in the oven for 4-5 hours until tender and the meat is falling off the bone. In the last 30 minutes, remove the foil to allow the meat to become charred and crisp.
3
Place the red onion in a bowl, add in the lemon juice and salt and massage gently until slightly tender. Set aside.
4
To pickle the cucumber: half lengthways and slice thinly on the diagonal and place in a wide dish. Combine all the other pickling ingredients in a pan and bring to the boil. Stir until the sugar dissolves. Pour over the cucumber and allow to sit for at least an hour before serving.
5
To make the aioli: Whisk together the egg yolk, garlic, dijon and lemon juice in a large mixing bowl. You can use an electric hand mixer for this or manually. Continue to whisk while you slowly pour the oil into the egg mustard mix until fully incorporated. You can whisk in a little water as you go if you see it is not incorporated into the oil fully. Season to taste.
6
Serve the lamb on plates alongside the rocket, cucumber, pickled red onion and aioli.