Place chiles on a foil-lined baking sheet; broil 10 minutes or until blackened, turning occasionally.
Place in a zip-top plastic bag; seal.
Let stand 15 minutes. Peel chiles; cut in half lengthwise. Discard seeds and membranes; slice into strips to measure 2/3 cup.
Place a large skillet coated with cooking spray over medium heat until hot.
Add 1 cup sliced onion; cook 10 minutes or until golden brown, stirring frequently. Stir in chicken and 1/3 cup chiles; spoon chicken mixture into a bowl.
Steam spinach leaves, covered, 5 minutes or until wilted.
Place spinach in a colander, pressing with the back of a spoon until barely moist.
Preheat oven to 35
Wipe skillet with paper towels, and recoat with cooking spray.
Place over medium-high heat.
Add 1/2 cup sliced onion and chopped green onions, and saute 3 minutes. Stir in ground cumin and minced garlic, and saute 30 seconds.
Combine masa harina and broth.
Add masa mixture, chopped cilantro, cream cheese, and salt to pan, and bring to a boil. Reduce heat, and simmer 5 minutes or until cheese melts, stirring constantly.
Place the cheese mixture, 1/3 cup chiles, and spinach ina food processor, and process until smooth. Strain spinach mixture through a colander into a bowl, and discard solids.
Divide the chicken mixture evenly among tortillas, and roll up.
Pour 1/2 cup spinach sauce in bottom of an 8-inch square baking dish coated with cooking spray. Arrange the filled tortillas on top of spinach sauce.
Pour the remaining spinach sauce over tortillas. Cover and bake at 350 for 10 minutes or until enchiladas are thoroughly heated.
