Preheat your oven to 350°F (175°C). Lightly grease your 9x13 inch baking dish with butter or non-stick spray to ensure the casserole doesn't stick.
Steam the broccoli florets until they are tender but still bright green, about 4-5 minutes. You can do this on the stove with a steamer basket or in the microwave with a little water in a covered bowl. Set aside.
In a large mixing bowl, combine the cooked white rice, shredded chicken, steamed broccoli, shredded cheddar cheese, cream of chicken soup, milk, garlic powder, onion powder, and salt and pepper. Gently fold everything together until well combined. This mixture is creamy and hearty, the perfect base for our bake.
Spread the mixture evenly into the prepared baking dish, smoothing the top with a spatula to create an even layer.
In a small bowl, mix the crushed Ritz crackers with the melted butter until the crumbs are evenly coated. Sprinkle this buttery cracker mixture evenly over the top of the casserole to form a golden, crunchy crust once baked.
Bake uncovered in the preheated oven for 25-30 minutes, or until the casserole is bubbly around the edges and the Ritz topping is golden brown. If you notice the topping browning too quickly, loosely cover the dish with aluminum foil and continue baking.
Remove the bake from the oven and let it rest for 5 minutes before serving. This allows the flavors to meld and the casserole to set for clean, hearty servings.
