Preheat oven to 325 degrees.
Cut up the chicken, reserving the neck and back for stock if you like. rub the legs, wings, and breasts with salt and pepper and brown in olive oil in a dutch oven or other large oven-proof pan. Remove the chicken to a plate and put the onions, and cinnamon in the pot. After a few minutes add the paprika, cumin, ginger, garlic, and coriander and saute five minutes. Add the mustard greens and preserved lemon and cook until greens have wilted.
Pour in 1 cup of stock. Put the chicken back in the pot and add cardamom, saffron, and ras el hanout. Pour in more stock until chicken is mostly covered (about another cup). Salt to taste.
Bring to a simmer and cook 3-4 minutes, then transfer to the preheated oven for 1 - 1.5 hours. Liquid will reduce and meat should be falling from bones. Find and discard the cinnamon and cardamom. Let rest for 10 minutes and serve over rice.
Spice measurements are estimates; season to taste.