Use your fingers to crumble the saffron threads into the chicken broth and stir to dissolve. Set aside.
On a platter, season the flour with ½ tsp salt and ¼ tsp black pepper. Dredge the chicken through the seasoned flour until fully coated.
Heat 1 tbsp oil in a large skillet or Dutch oven over medium heat.
Sear the lemon slices until browned slightly on both sides, about 3 to 5 minutes. Remove from skillet and set aside.
In the same skillet, heat the remaining 2 tbsp of oil over medium-high heat. Sear the chicken, skin side down, until golden and crispy, about 5 to 6 minutes. Transfer to a plate. (The chicken will not be fully cooked at this point).
Add the onion to the skillet and cook until soft and translucent, about 4 to 6 minutes. Add the garlic and cook for another 30 seconds, stirring occasionally.
Stir into the onions the paprika, cumin, ginger, cinnamon, coriander, turmeric, and ½ tsp salt. Stir until combined and very fragrant, about 1 minute.
Add the stock-saffron and use a wooden spoon to deglaze the pan by scraping up any bits that are stuck to the bottom of the skillet.
Place the chicken, skin-side up, throughout the pan. Cover and simmer for 30 minutes.
Remove the lid and stir in the olives, lemon juice, zest, and cilantro. Cover and simmer for 10 more minutes.
Serve over couscous and garnish with remaining cilantro and chopped pistachios.