Meanwhile, steam the cauliflower florets in a steamer basket over boiling water until they are tender yet still maintain some firmness, approximately 5-7 minutes. Once done, drain and set aside to cool slightly.
In a large mixing bowl, combine the shredded chicken, buffalo sauce, Greek yogurt, garlic powder, onion powder, paprika, and season generously with salt and pepper. Stir everything together until all the ingredients are well blended and the chicken is fully coated in the mixture.
Carefully fold in the steamed cauliflower florets into the chicken mixture until they are evenly incorporated. Be gentle to keep the cauliflower intact.
Transfer the entire mixture into a greased 9x13-inch casserole dish, spreading it out evenly for uniform cooking.
Top the casserole with an even layer of shredded cheddar cheese, followed by the blue cheese crumbles, if you choose to add them.
Place the casserole in the preheated oven and bake for 20-25 minutes, or until the cheese is melted, bubbly, and has turned a lovely golden brown.
After baking, remove the casserole from the oven and let it cool for a few minutes. Before serving, sprinkle with sliced green onions for a fresh pop of color and flavor.
Notes
Serve hot with crunchy celery sticks or a light green salad.