Preheat the oven to 350°F and grease a mini muffin pan with nonstick cooking spray. Place the wonton wrappers in the muffin cups and press them down to form cups. Lightly spray the wrappers with nonstick cooking spray.
In a mixing bowl, stir together the cooked shredded chicken, softened cream cheese, buffalo wing sauce, and shredded cheddar cheese until well combined.
Scoop the chicken mixture evenly into each wonton cup.
Bake for 10–12 minutes, or until the wonton wrappers are golden brown.
Top with crumbled blue cheese and sliced green onions, then serve.