Preheat the oven to 200°C, 400°F, Gas 6.
Rub the lamb with olive oil and the spice mix then roast in the oven for 8-12 minutes depending on thickness. The meat should remain pink in the centre. Set aside to rest.
Make the fattoush: Simply mix all the dry ingredients together in a large bowl, then toss with the lemon juice and olive oil. Sprinkle with sumac and seasoning and leave to infuse while the lamb is resting. To serve, slice the lamb thickly and serve alongside the salad.