This is the easiest and quickest dinner I have ever made, and I always have the ingredients handy for last minute hunger pangs! I love it because you can double or triple it very easily depending on how many people are arriving. I usually serve this with a pot of charro beans and some Mexican rice.
Preheat the oven to 350 degrees. Grease a 9 x 13 Pyrex dish and generously cover the bottom with crushed tortilla chips.
Debone and shred cooked chicken; spread over chips. Cover with at least 2 cups (I usually buy the tomatillo sauce in at least a pint container); then cover heavily with the cheese.
Cover with foil and bake for about 30 minutes or until bubbly. You can make this ahead of time since the chips are supposed to dissolve with the salsa and make a type of crust; therefore, it doesn't matter if they get soft!
If you are a sour cream lover (which I am), a dollop of sour cream and some chopped green onions on top make it a pretty presentation.