Place the ginger, garlic, coriander leaves, lemon juice and zest and oil into a mini chopper/blender or pestle and mortar and blend to a paste.
Place the paste into a small bowl.
Heat a small frying pan over a medium heat, add the cumin, cloves, black pepper, fennel, cinnamon, paprika and salt and gently toast until fragrant. Stirring to prevent the spices burning. This will take approx. 1-2 minutes.
Allow to cool and then add to the fresh paste, stir well.
Ensure the leg of lamb fits into your stoneware bowl, if it appears too big you will need to remove some of the tapered end using a meat cleaver.
Score the surface of the lamb with a sharp knife making 2cm slits in the skin.
Rub the marinade all over the lamb ensuring you cover both top and underside. Ideally this can be done 24hrs beforehand to gain maximum flavour. Cover with food wrap and store in your refrigerator.
Place the lamb and surplus marinade into your stoneware bowl. Cover and cook on Low for 6-7 hours or High for 5-6 hours until tender.
If you like a crispier finish to your lamb, place the stoneware bowl into a hot oven for crisping once the cooking time has finished.
Delicious served carved into slices, with hot flat breads, tzatziki, harissa sauce and crisp salad leaves.