How to Make It
In a large enameled cast-iron casserole, heat 2 tablespoons of the olive oil. Add the minced onion and cook over moderately high heat, stirring occasionally, until just starting to brown, about 5 minutes. Scrape into a bowl.
Season the chicken breasts with salt and pepper. Add the remaining 2 tablespoons of olive oil to the casserole and sear the chicken in 2 batches, until browned, about 3 minutes per side. Return all of the chicken to the casserole.
Add the cinnamon sticks, minced parsley and cilantro, ginger, saffron, sautéed onion, white wine and stock to the casserole and bring to a boil. Reduce the heat to moderate, cover and simmer the chicken for 30 minutes. Stir the olives and preserved lemon into the casserole and simmer until the chicken breasts are cooked through, about 15 minutes longer. Transfer the lemon confit chicken to a warm platter and cover with foil.
Boil the cooking liquid in the casserole over high heat until reduced by half and slightly thickened, about 10 minutes. Discard the cinnamon sticks. Spoon the sauce over the chicken, garnish with the cilantro sprigs and serve.