Preheat your oven to 350°F (175°C).
In a large mixing bowl, combine cooked rice, cubed chicken, and broccoli florets.
In another bowl, mix cream of chicken soup, milk, garlic powder, salt, and pepper.
Pour the soup mixture over the rice and chicken mixture and stir until well combined.
Transfer the mixture to a greased 9x13 inch baking dish.
Sprinkle shredded cheddar cheese evenly on top.
In a small bowl, mix breadcrumbs with olive oil and sprinkle over the cheese.
Bake in the preheated oven for 25-30 minutes or until golden and bubbly.
Remove from oven and let it rest for 5 minutes before serving.
Garnish with fresh herbs if desired and enjoy!