Preheat the oven to 350°F. Lightly oil a large, shallow casserole.
Ladle 3⁄4 cup of enchilada sauce into the casserole and spread it evenly across the bottom. Set aside.
Put the chicken into a large bowl, add 1⁄2 cup of enchilada sauce, and stir. Add the sour cream, parsley, onion, and salt and pepper, to taste. Stir and set aside.
Soften the tortillas.
Working with one tortilla at a time, spread a portion of chicken filling across the center. Sprinkle with 2 tablespoons of cheese and roll up the enchilada. Place in the casserole, seam side down. Repeat with the remaining tortillas.
Spoon the remaining sauce over the enchiladas. Sprinkle with the remaining cheese and bake for 25 to 30 minutes, or until bubbly.