In a large bowl, combine olive oil, lemon juice, oregano, cumin, coriander, turmeric, paprika, garlic powder, onion powder, cayenne (if using), salt, and black pepper to create the marinade.
Add chicken thighs to the marinade, ensuring they are well-coated. Cover and refrigerate for at least 1 hour, or up to overnight for maximum flavor.
Preheat your oven to 400°F (200°C). Arrange marinated chicken thighs on a baking sheet lined with parchment paper. Bake for 25-30 minutes or until the internal temperature reaches 165°F (74°C).
While the chicken cooks, prepare the rice. In a saucepan, combine rinsed basmati rice, water, butter, and salt. Bring to a boil, then reduce heat to low, cover, and simmer for 18-20 minutes until the water is absorbed and rice is tender.
Once cooked, fluff the rice with a fork and let it rest, covered, for 5 minutes before serving.
Slice the cooked chicken into thin strips. Serve over the prepared rice, drizzled with your favorite white sauce and hot sauce.