Drain the canned green chilis and place them in between paper towels and lightly press down. You need the chilis to be as dry as possible so you do not have too much moisture in your filling mixture.
In a small bowl combine the canned green chilis, cheddar cheese, green onions and softened cream cheese, set aside.Slice each chicken breast lengthwise so that the breast folds open (be sure not to slice all the way through)
Spread the cheddar mixture on one side of the chicken and fold the other side over, secure with a toothpick.Lightly sprinkle the cajun seasoning on each side of the chicken.Place in a greased baking dish. Bake 25-30 minutes until the chicken is cooked through.