Season the turkey: in a large bowl, combine the turkey with 1 tbsp olive oil, ginger, turmeric, paprika, cumin, cinnamon, salt and pepper. Let it marinate for 15 to 30 minutes if possible.
Brown the base: in a Dutch oven or a large, deep skillet, heat the remaining oil. Add the onions and sauté for 5 to 7 minutes, until softened. Add the garlic and cook for 1 minute.
Sear the turkey: add the turkey pieces and brown them lightly on all sides.
Simmer, add: the broth, half of the chopped cilantro and parsley, the preserved lemon. Cover and simmer over low heat for about 35 to 45 minutes, until the turkey is very tender.
Finish the tagine. Add the olives during the last 10 minutes of cooking. Taste and adjust the salt. Be careful: the preserved lemon and olives are already quite salty.
Serve. Add the remaining fresh herbs on top. Serve with: couscous, Moroccan bread, rice, or steamed potatoes.