These are a great way to utilize the rotisserie chickens from the grocery store or leftover cooked chicken. Good way to get some veggies in, too! Use a measuring cup to ensure that the portions are all about the same size.
Filling: Heat oil in large nonstick skillet over medium-high heat. Add onion and cook until clear.
Add chicken, chilies, cayenne and cumin, and cook for 2 minutes, stirring constantly.
Remove from heat and stir in corn, spinach, sour cream, 1 cup monterey jack cheese and salt. Adjust seasonings if necessary.
Lightly spray a 13x9 inch pan and a piece of aluminum foil big enough to cover it with non-stick spray.
Microwave 6 tortillas wrapped in damp paper towels on high about 1 minute, until soft enough to roll. Keep warm during assembly by covering with clean kitchen towel. Place a rounded 1/3 cup filling down each tortilla, roll into a cylinder and place seam side down in pan. Repeat with all 12 tortillas. You will probably have two layers of enchiladas in the pan.
For sauce: stir the taco sauce and sour cream together in a small bowl. Pour evenly over enchiladas in pan. Bake, covered with foil for 30 minutes at 350 degrees, sprinkle with cheese and cilantro, and bake uncovered 10 minutes more or until cheese is melted.