Preheat oven to 350 degrees F.
With an electric mixer, beat the cream cheese and the ranch dressing until well mixed.
Add the onion and cheeses and fold in until well combined.
Spread this mixture into a pie dish or a small baking dish
In a small bowl combine the chicken and the buffalo wing sauce until well combined.
Spread this over the first layer.
In another bowl combine the Monterey and cheddar cheese. Spread over the chicken layer.
Place this into the preheated oven and bake for 15 to 20 minutes or until the cheese is melted and the ingredients are bubbling.
Serve with crackers, chips, veggies, or whatever you like.