Preheat your oven to 375F and ensure the rack is in the middle position.
In a large bowl, stir together the cream of chicken soup and chicken broth until fully combined.
Grease a 9×13 casserole dish to prevent sticking.
In the greased casserole dish, add the uncooked rice, cooked chicken, frozen vegetables, garlic powder, onion powder, Italian seasoning, pepper, scallions, and 1 cup of the cheddar cheese. Mix everything together gently.
Pour the soup and broth mixture over the rice and chicken mixture. Toss until well coated and smooth into an even layer in the dish.
Cover the dish tightly with foil and bake for 45 minutes.
Remove the foil, sprinkle the remaining cheese on top, and bake uncovered for an additional 10-15 minutes, until the cheese is melted and the rice is soft.
Notes
Choose flavorful cooked chicken for best taste.
Test the rice and cover and return to the oven if needed.
Allow the casserole to cool for about 5-10 minutes before serving.