Place the chicken pieces in a large skillet with high sides and a lid that will hold all the ingredients. Mix the salt and pepper together and rub it all over the chicken pieces. Let them rest for 15 minutes.
Mix the ginger, paprika, and saffron and sprinkle evenly over the meat. Then mix the onion purée and the tomato purée and gently pour over the spices. Make sure the spices and purée are spread evenly over the chicken. Drizzle the combined oil and butter over the mixture and let it sit for 15 minutes.
Bring the water to a boil and carefully pour it down the side of the pot rather than directly on top of the mixture. Place the pot on the stove and bring to a simmer. Cover and cook, turning the pieces several times, for about 30 minutes or until the chicken is cooked. Add more boiling water if the sauce starts to stick to the pan.
Remove the chicken from the pot, place on a warm plate, and tent it with foil. Add the olives and the preserved lemon rind to the liquid in the pot. It should be the consistency of thick cream. Simmer for a few minutes if it is too thin.
Place the chicken on a serving dish, pour the sauce overtop, and sprinkle with the coriander.
Preserved Lemons
6 lemons
approximately ½ to ¾ cup (120 to 180 mL) kosher salt
At least 3 weeks before they are needed, cut the lemons in quarters almost all the way through, but making sure they are still joined at the bottom. Rub lots of salt onto the cut sides and close them up again. Place the lemons in a clear jar, place a heavy weight, such as a washed stone, on top of them, close the jar, and refrigerate. The lemons will start to extrude juice. Leave them for at least 3 weeks.