Preheat oven to 350°F. Coat a 8x8" baking dish or cast iron skillet with cooking spray.
In a medium bowl beat together the cream cheese, sour cream, Ranch dressing, hot sauce and half the blue cheese crumbles (reserve remaining for garnish) until smooth.
Add the chicken and toss to coat and mix thoroughly. Transfer to baking dish or oven safe skillet. Bake 20 minutes until bubbling hot.
Finely dice the green onion and scatter on top with reserved blue cheese crumbles. Serve hot with crackers, bread of choice or celery and carrot sticks.