Preheat your oven to 350°F (175°C).
In a large mixing bowl, combine the cooked chicken, uncooked rice, chicken broth, cream of chicken soup, frozen mixed vegetables, garlic powder, onion powder, thyme, salt, and pepper.
Stir until well combined.
Pour the mixture into a greased baking dish.
Cover with foil and bake for 45 minutes.
Remove the foil and bake for an additional 15 minutes, or until the rice is tender and the top is slightly golden.
Garnish with fresh herbs if desired and serve warm.