1. Roll the meat in Tabil and black pepper.
2. In a casserole, heat the olive the oil over medium heat.
3. Brown the meat with the onions until coated with a syrupy gravy, 5 to 6 minutes. Add the tomatoes, 1 cup of the water, the Harissa, chickpeas, and cayenne, and bring to a boil, stirring.
4. Reduce the heat to low, cover and cook until the meat is tender, about 1 1/2 hours.
5. Add the remaining 1/2 cup of water, the turnips, parsley, spinach, and salt, season with black pepper, and cook until the turnips are easily pierced with a skewer, about an hour.
6. Stir in the lemon juice and serve.