Preheat the oven to 350°F (180°C).
Season the chicken: In a large mixing bowl, whisk together the olive oil, salt, black pepper, smoked paprika, thyme, oregano, and garlic granules. Add the chicken thighs and coat them well. If time allows, marinate for 15-30 minutes.
Prepare the rice: In an 8×12-inch (20x30cm) baking dish, combine the diced onion, minced garlic, olive oil, melted butter, hot stock, hot water, uncooked rice, salt, and pepper. Stir to mix.
Assemble the dish: Place the seasoned chicken thighs on top of the rice mixture.
Bake covered: Cover the baking dish tightly with foil and bake for 30 minutes.
Bake uncovered: Remove the foil, spray the chicken with oil, and return the dish to the oven. Bake for another 30 minutes. For crispy, golden edges, broil the chicken for a few minutes at the end.
Rest and serve: Remove the dish from the oven and let it rest for 10 minutes. Fluff the rice with a fork (removing the chicken if needed, then placing it back in). Garnish with fresh herbs and serve warm.
Notes
Chicken thighs: Bone-in, skinless chicken thighs are ideal as they cook in the same time as the rice. Keeping the skin on may make the rice greasy.
Stock and water: Ensure both are hot to help the rice cook evenly.
Rice options: Use long-grain varieties like basmati or jasmine. Avoid risotto, paella, or quick-cooking rice, as they may turn mushy. Brown rice can be used but requires more liquid and a longer cooking time.
Seasonings: Feel free to adjust the spice blend to suit your taste.
Baking dish: An 8×12-inch (20x30cm) dish works best, but a slightly larger one is also suitable.