Preheat oven to 350°F. In a large bowl add the diced chicken, diced green chiles, sour cream, and softened cream cheese and mix together.
Add a cup and a half of the green enchilada sauce and half of the cheese, mix well. Taste, and add more sauce, salt, and pepper if needed.
Add a couple of tablespoons to the bottom of the baking pan, spread it around so a little bit is everywhere.
Place a tortilla in the pan and add small spoonful of the enchilada sauce.
Spread a couple of heaping spoonfuls of the chicken mixture into the center of the tortilla. Roll tightly and place up against the side of the pan.
Repeat steps six and seven until the pan is full. Spread the remaining sauce on top of the rolled enchiladas and cover with the remaining cheese.
Cover with aluminum foil and bake for 25 minutes. Then removed the foil and cook for another 5 minutes or until the cheese has melted and begun to turn golden brown.
Notes
Soften the cream cheese first. Room temperature cream cheese blends smoothly into the filling. Cold cream cheese leaves lumps that won't melt evenly during baking.
Don't overfill the tortillas. Two heaping spoonfuls per tortilla is plenty. Overfilling makes them impossible to roll tightly and they'll burst open in the oven.
Sauce the bottom of the pan. A thin layer of enchilada sauce on the bottom prevents the tortillas from sticking and drying out during baking.
Cover with foil first. Baking covered for the first 25 minutes lets the filling heat through without burning the cheese. Removing the foil for the last 5 minutes gives you that golden, bubbly top.
Corn tortilla technique. If using corn tortillas, dip each one in warm oil for a few seconds. The heat gelatinizes the starches in the corn, making the tortillas pliable enough to roll without cracking.
Use a cast iron baking dish. Cast iron holds and distributes heat more evenly than glass or ceramic, giving you better edge browning and keeping the enchiladas hot at the table.