Heat oven to 350°F. Spray 13x9-inch (3-quart) glass baking dish with cooking spray. In large bowl, mix ham, sour cream, green chiles and 2 cups of the cheese.
Spoon about 1/3 cup ham mixture evenly down center of each tortilla. Fold sides of tortilla over filling; place seam side down in baking dish. Pour enchilada sauce over filled tortillas.
Spray sheet of foil with cooking spray; cover dish tightly with foil, sprayed side down. Bake 30 to 35 minutes or until thoroughly heated. Uncover; sprinkle with remaining 1/2 cup cheese. Bake uncovered 5 minutes longer or until cheese is melted. If desired, serve with shredded lettuce and chopped tomatoes.