This is one of the fastest and easiest enchilada dishes I know how to prepare, especially when I use the Rotisserie Chicken shortcut. Most of the flavor comes from the onion, green chiles, and cilantro, but I like to add some jalapeno slices on top for a little more kick.
The filling and the sauce are nearly identical. The filling has the chicken chunks and the sauce has some milk. I find that each enchilada needs about two tablespoons of filling.
This is the arrangement that worked best for us. Just make sure that you have one flat layer that fills whatever pan that you choose. I don't care what the recipe says, be sure to use enough cheese to really cover the enchiladas and sprinkle a bit of chopped cilantro to add some color. We finished cooking the dish by broiling it for two minutes so that the cheese was golden, brown and delicious.