01 - Set oven temperature to 375°F (190°C).
02 - In a large bowl, combine softened cream cheese, sour cream, and ranch dressing; blend until smooth.
03 - Fold in buffalo wing sauce, shredded chicken, half of the cheddar cheese, and blue cheese if using.
04 - Transfer mixture evenly into a 9-inch baking dish or oven-safe skillet.
05 - Sprinkle remaining shredded cheddar cheese evenly over the top.
06 - Bake for 20 to 25 minutes until hot and bubbly throughout.
07 - Remove from oven and cool for 5 minutes; garnish with sliced green onions.
08 - Serve warm alongside celery sticks and tortilla or potato chips for dipping.