Preheat your oven to 375°F (190°C).
In a large oven-safe skillet, heat olive oil over medium heat.
Add sliced onions and cook until caramelized, about 15 minutes.
Season the chicken thighs with salt, pepper, and thyme.
Push the onions to the side and add the chicken thighs to the skillet.
Sear the chicken for 5 minutes on each side until golden brown.
Stir in the rice and pour in the chicken broth.
Bring the mixture to a boil, then cover and reduce heat.
Transfer the skillet to the preheated oven.
Bake for 25-30 minutes, until the rice is cooked and the chicken is tender.