Preheat the oven to 375°F.
In a large bowl, mix the softened cream cheese, sour cream, buffalo sauce, ranch seasoning, and 1 cup of shredded cheddar until smooth.
Fold in the shredded cooked chicken until evenly coated.
Spread the mixture into a greased 8-inch baking dish or small oven-safe skillet.
Sprinkle the remaining 1/2 cup cheddar cheese over the top.
Bake for 18 to 20 minutes, until hot and bubbly around the edges.
Remove from the oven and let rest for 5 minutes.
Garnish with sliced green onions and serve warm with tortilla chips, celery, carrots, or crackers.