Preheat oven to 350°F (180°C).: You will notice the oven hum as it warms, and the air inside shifts from neutral to dry warmth, which is essential so the rice starts cooking evenly as soon as it hits the hot baking dish. Setting the oven early prevents temperature shock when you place a full dish inside, and it ensures the timings in this recipe hold true. A common pitfall is skipping preheat which can leave the rice undercooked or the chicken overdone, so always wait until the oven shows it has reached temperature.
In a shallow bowl, mix together the olive oil, sugar, oregano, paprika, onion powder, garlic powder, thyme, salt and pepper. Add the chicken and coat each piece evenly with the seasoning. Set aside, allowing the flavours to absorb into the meat. If time allows, marinade overnight for a deeper flavour.: The aroma of the spices hits you first when mixed with oil, and that scent clings to the chicken as you rub it in, which helps create a seasoned crust as it bakes. Letting the seasoned pieces rest allows salt to penetrate and the spices to marry with the meat, improving depth. Avoid piling pieces on top of each other when marinading, because uneven contact can yield pockets of blandness.
Spray a large baking dish (10-inch x 15-inch OR 25 x 35 cm) with nonstick cooking oil spray. Add the onion, garlic, oil, salt, pepper, HOT boiled broth, hot water and butter into the dish. Mix well to melt the butter and combine. Stir in the rice.: When the hot broth hits the dish the butter melts with a gentle hiss, and the scent of softened onion and garlic blooms. Stirring at this stage warms each grain so they begin absorbing liquid immediately and evenly, avoiding cold pockets that cause uneven cooking. A frequent mistake is adding cold liquid which drops the overall temperature and can lead to undercooked rice.
Arrange thighs in the dish over the rice, cover with foil and bake for 30 minutes. Uncover, spray chicken with oil and bake for an additional 25-30 minutes or until the chicken is cooked right through to the bone and rice is soft. Change oven setting to broil to brown the chicken and crisp rice (only needs 3-5 minutes).: The initial covered bake creates steam that cooks the rice gently while the chicken releases juices into the grains. After uncovering, the skinless thighs will start to color, and the top of the rice will firm. Switching to the broil briefly gives you that sizzling browning, and you will smell a toasty, caramel scent when it’s working. A common error is leaving the foil off too early, which dries the rice and leaves it chewy.
Remove chicken thighs, mix the rice through, then arrange the chicken back on top of the rice. Cover and allow it to rest for 10 minutes to set all of the flavours in the hot dish. The rice will finish off cooking while resting.: Resting lets the internal juices redistribute, making each bite juicier, and the rice absorbs any remaining liquid, finishing its texture. While resting, the surface steam settles, and the dish cools enough to be served comfortably. Cutting into the meat right away can cause juices to run out, drying the pieces, so resist the urge to slice immediately.
While chicken is resting, prepare mushrooms (OPTIONAL): Heat butter in a pan over medium-high heat. Sauté garlic until fragrant (30 seconds) and add mushrooms; cook until softened. Stir in 2 tablespoons of chives and season with salt and pepper.: Heat butter in a pan over medium-high heat. Sauté garlic until fragrant (30 seconds) and add mushrooms; cook until softened. Stir in 2 tablespoons of chives and season with salt and pepper : In the pan you will hear a steady, lively sizzle as mushrooms release moisture and then brown. Properly cooked mushrooms become tender and slightly caramelized, contributing an earthy depth that contrasts the fluffy rice. Cook them until their liquid reduces, or else they can make the rice soggy when combined. A mistake here is crowding the pan, which causes steaming instead of browning.
Transfer chicken onto a plate; fluff rice with forks, then mix the mushrooms through the rice. Arrange chicken back onto the rice in the dish, garnish with remaining chives and chopped parsley. SERVE and enjoy!: Fluffing with forks separates the grains, and as you fold in the mushrooms you will see glossy bits and flecks of herb distributed throughout. Returning the chicken to the top lets the juices mingle on the surface, creating pockets of extra flavor. Serve while warm so the texture contrast between tender meat and fluffy rice is pronounced. Reheating later can flatten textures, so store gently and reheat only once for best results.