Preheat your oven to 350°F (175°C). Grease a 9x13 inch baking dish lightly with butter or cooking spray. This prevents sticking and makes cleaning easier later.

Bring water to a boil in a large pot. Add broccoli florets and cook for two minutes. Drain quickly and rinse with cold water to keep bright green color.

In a saucepan, melt butter over medium heat. Add chopped onion and cook until soft. Stir in flour and cook one minute. Slowly add milk and broth. Stir until thick.

Reduce heat to low. Add shredded cheddar cheese slowly. Stir until melted and smooth. Add salt, pepper and garlic powder. Mix well to combine flavors evenly.

In a large mixing bowl, add cooked rice and shredded chicken. Add cooked broccoli. Pour the creamy cheese sauce over everything. Stir gently until well coated.

Pour the mixture into the prepared baking dish. Spread evenly using a spoon. Sprinkle extra cheese on top if desired. Add breadcrumbs for a crispy topping.

Place the dish in the oven. Bake for 30 to 35 minutes. The top should look golden and bubbly. Let it rest for five minutes before serving.

Scoop the casserole into plates while warm. Enjoy the creamy texture and cheesy flavor. This Pioneer Woman Broccoli Chicken Rice Casserole Recipe is perfect for family dinners.