Heat oven to 375 degrees. Coat one 4-quart or two 2-quart baking dishes with nonstick cooking spray. If using 1 dish, spread 1/3 cup of the enchilada sauce in bottom. If using 2 dishes, spread 3 tbsp of the enchilada sauce in bottom of each dish.
In a bowl, combine chicken, 1 cup of the shredded cheese and 3/4 cup of the enchilada sauce.
Spread 2 tsp Neufchâtel on a tortilla. Spoon 2 to 3 tbsp chicken mixture in a strip in center of tortilla. Roll up tightly to enclose filling; transfer to prepared dish(es). Repeat with remaining tortillas, cream cheese and chicken mixture to yield 16 enchiladas.
Pour remaining sauce over enchiladas, dividing evenly between dishes. Top with remaining cheese. Bake at 375 degrees for 20 minutes. Increase temperature to 400 degrees and bake an additional 5 minutes, until cheese begins to brown slightly. Garnish with jalapeño slices, cilantro
