Preheat oven to 160 C / 320F
Put all of the spices, preserved lemon, seeds, zaatar and olive oil into a bowl and mix into a loose paste. Rub this all over the lamb and spread the rest on top.
Put the lamb shoulder into an oven dish . Add a cup of water and cover well with a lid or foil. Put into the oven. Check at 2 hours but 3.5 to 4 hours will be the point where the lamb is soft and falling from the bone.
For the Salad. I like to make sure the onion in the salad is soft and delicious and not over powering. I rinse it in boiling water ( poured over and left to sit 30 sec and then drain)
Put the chopped onion in a bowl and add the lemon juice and tomato ( with all of the juice). Mix in the quinoa, mint and parsley and olive oil. Mix together and taste, seasoning with salt, pepper and more lemon juice if needed.
Put the tahini , garlic, lemon juice and cumin into a bowl and start to mix. The mixture will become firm. Add a tablespoon of water at a time as you stir until a nice smooth sauce is formed. You will need salt . Taste and add more seasoning or lemon to bring out the flavours.
When the meat is ready. Put onto the top of the stove and rest. Once I have cut the Lamb I turn on the stove top and reheat the juices and the bits of spice crust and juices left in the dish and left over when cutting. If you wish to add a little more stock and mix around you will have a lovely sauce.
Serve the lamb with the Quinoa salad and tahini. This would also go with roast pumpkin, sweet potato or boiled or mashed potatoes.