Mix soup, chiles, sour cream, and milk together in a large skillet. Heat until it bubbles.
Remove from heat and dip tortillas into mixtures one at a time.
Place chicken onto tortillas and roll, then place into a baking dish sprayed with cooking spray. Cover with foil.
Bake at 350° for 30 minutes. Remove from oven, sprinkle with grated cheese, and serve with additional sour cream and guacamole, if desired.