Preheat the oven to 350°F (175°C).
In a large skillet, melt the butter over medium heat. Season the chicken breasts with garlic powder, onion powder, salt, and pepper. Sauté the chicken for about 6-7 minutes on each side until golden. Remove from heat and cut into bite-size pieces.
In a mixing bowl, combine cooked rice, cream of mushroom soup, cream of chicken soup, sour cream, and chicken broth. Stir until well combined.
Spread half of the rice mixture evenly in the bottom of the greased baking dish. Layer the sautéed chicken pieces on top, then top with remaining rice mixture.
Cover the baking dish with aluminum foil and bake in the preheated oven for 30 minutes.
Remove the foil, sprinkle shredded cheddar cheese on top, and bake for an additional 15 minutes, or until the cheese is melted and bubbly.
Remove from the oven, let it cool for a few minutes, and garnish with chopped parsley before serving.