Sautéed spinach and potatoes roasted with ground coriander
Mix together all the ingredients for the spice mix. Set aside 1 tablespoon of the mix to add to the gravy, then rub the remainder all over the lamb. If possible do this the day before and leave the lamb in the fridge overnight.
Heat the oven to Gas Mark 5, 190°C (375°F).
Take the lamb out of the fridge 20-30 minutes before cooking to allow it to get to room temperature. Place the lamb in a roasting tin and place in the oven, uncovered, for 1¼ hours. The lamb will be cooked medium at this stage. Remove from the oven, cover loosely in foil and allow to rest for up to 30 minutes. Reserve the juices in the pan.
To make the Coriander Yoghurt: While the lamb is cooking combine all the ingredients for the coriander yoghurt. Taste and season with a little salt and black pepper.
Boil up the juices in the roasting tin along with a little water or wine, the reserved spice mix and a squeeze of lemon juice. Taste and season, then strain and serve with the lamb.