In a small bowl, mix together 3/4 teaspoon salt, 1/4 teaspoon pepper, cumin, red pepper flakes, lemon juice, olive oil, cilantro and garlic.
Rub the chicken with the mixture. Let sit in the refrigerator covered for 1 hour.
Combine the tomatoes with ½ teaspoons salt.
Place half of the tomatoes, half of the bell pepper and half of the preserved lemons on the bottom of a tagine or heavy stewing pot.
Place the chicken on top.
Top with the bell peppers, then preserved lemons and tomatoes.
Bring to a boil over high heat, reduce to the heat to medium low and simmer 20 minutes.
To serve, spoon the chicken, vegetables and sauce into soup bowls and place a spoonful of the Walnut Chermoula onto the top.
Walnut Chermoula
In a blender or food processor, puree the cumin, paprika, turmeric, cayenne, garlic, cilantro, parsley, lemon juice, olive oil, ½ teaspoon salt and ¼ teaspoon pepper until smooth.
Add the walnuts and set aside.
Serving
Plate the chicken alongside some cauliflower rice with a bit of chermoula on the side.