Preheat your oven to 350°F (175°C) and coat a 9x13 inch casserole dish with cooking spray or olive oil.
In a large mixing bowl, combine the shredded chicken, cooked quinoa or rice, buffalo sauce, ranch dressing, broccoli florets, corn, garlic powder, onion powder, and half of the shredded cheddar cheese. Mix until everything is well coated.
Season the mixture with salt and pepper to taste.
Pour the chicken mixture into the prepared casserole dish and spread it evenly.
Sprinkle the remaining cheddar cheese on top of the casserole. If using, sprinkle crushed tortilla chips over the cheese for added crunch.
Bake in the preheated oven for 25-30 minutes, or until the cheese is bubbly and slightly golden.
Once baked, remove from the oven and let it sit for about 5 minutes before serving.
Garnish with chopped green onions on top for a fresh finish.
Notes
Adjust the buffalo sauce based on your spice preference. Optional crushed tortilla chips add crunch.