First make the marinade. Place the spices, garlic, lemon juice, and cilantro in a small blender or mortar and grind until smooth. Add 5 tablespoons of olive oil, along with a generous pinch of salt and pepper, and blend again to mix well. Transfer the marinade to a large dish. Add the chicken and rub in the marinade, making sure that all of the chicken is covered. Leave to marinate for up to 2 hours.