Preheat oven to 350°F/175°C. (Unless you will be freezing them for later.)
Mix together the cream soup, vinegar, sour cream, 1 1/2 cups cheese, chilies and chicken broth.
Set aside 1 cup of sauce to put on top of the enchiladas. Add 1/4 to 1/2 cup milk to the sauce to thin it out to your desired consistency. You could also use additional chicken broth instead of milk. Add chicken and cilantro to remaining sauce.
Lightly fry corn tortillas in oil over medium heat on the stove. Just enough to soften the tortilla.
Fill tortillas with chicken filling and arrange in a 9 x 13 pan. If using 12 tortillas, use about 1/3 cup filling for each. Cover with the sauce that was set aside and sprinkle remaining shredded cheese on top.
Cover with foil, bake for 20-25 minutes, removing the foil for the last 5-10 minutes. Serve with your favorite enchilada toppings: avocado, sour cream, salsa, cilantro, guacamole, olives, etc.
For best results, freeze the sauce, cheese, and tortillas (not fried yet) separately in freezer bags, then thaw and assemble enchiladas when you are ready to serve them. Bake as directed above.
Alternatively, use any 9x13 pan you have on hand to put in the freezer. But if you are going to need the pan again soon I recommend using a disposable aluminum pan. Assemble the enchiladas, cover with foil, and place in the freezer.
TO PREPARE FOR SERVING:
Preheat oven to 350°F/175°C. Remove enchiladas from freezer, leave foil on pan and cook for about 30 minutes. Remove foil and cook additional 15-20 minutes, until bubbling and cheese completely melted.
Or thaw enchiladas in the refrigerator, then bake as directed above (for enchiladas that are not frozen).