Preheat your oven to 350°F. Scatter chopped onions and minced garlic across the base of your baking dish. Add butter to the center and bake for about 15 minutes until softened and fragrant. This step ensures your rice starts with a savory, buttery base.
While the onion and garlic bake, mix together the paprika, thyme, garlic powder, onion powder, salt, and pepper to create the chicken rub. Coat both sides of the chicken thighs with this seasoning blend.
Take the baking dish out of the oven. Stir the baked onion and garlic mixture to distribute evenly, then add the uncooked rice. Mix everything gently to incorporate the flavors.
Place the seasoned chicken thighs on top of the rice. Pour hot chicken broth and water around the chicken, ensuring the rice is submerged. Cover the dish tightly with foil.
Bake covered for 30 minutes to cook the rice and chicken evenly. Remove the foil, spray the chicken lightly with cooking oil for a golden finish, and bake uncovered for another 20 minutes. Once the liquid is fully absorbed, the dish is ready!
After removing the dish from the oven, allow it to rest for 5 minutes. Carefully fluff the rice with a fork, garnish with fresh parsley or thyme, and serve warm!