Combine half your cheese, cream of mushroom soup, cream of celery soup, rotel, green chilies, onion, and green onions in a large mixing bowl and mix up really good.
Add chicken to mixing bowl and mix well.
Shred tortillas and add to mix and mix well.
Put all of the mix into a 9×13 lightly oiled pan. Put the rest of the cheese on top and bake for about 25 minutes.
Let cool and serve! I like to garnish mine with more green onions, sour cream, and taco sauce! YUM!