In a large pot, boil the diced potatoes in salted water until tender, about 15-20 minutes. Drain and set aside.
In a mixing bowl, combine the shredded chicken with buffalo sauce, cream cheese, sour cream, garlic powder, salt, and pepper. Mix until smooth and well combined.
In a large baking dish, layer the cooked potatoes at the bottom. Pour the buffalo chicken mixture over the potatoes, spreading it evenly.
Sprinkle the shredded cheddar cheese on top of the buffalo chicken mixture.
Cover the baking dish with aluminum foil and bake for 25 minutes. Then remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and golden.
Remove from the oven and let it cool for a few minutes. Garnish with chopped green onions and drizzle with extra buffalo sauce if desired.
Notes
Rotisserie chicken works great for this recipe. Adjust buffalo sauce to taste.