In a medium size casserole dish, mix together the cream cheese, cheddar cheese, hot sauce and ranch dressing until smooth and creamy. Stir in the cut up chicken.
Cover the casserole dish with a lid and bake for 20-30 minutes. The dip should be creamy and the cheddar cheese melted.
Scoop into a serving bowl or, if desired, serve in the casserole dish. Sprinkle with crumbled blue cheese.
Serve warm with tortilla chips, crackers, celery or carrot sticks.