Preheat oven to 350 dgrees.
Combine the salsa verde and sour cream in a bowl, use a whisk to make a smooth sauce. Put in refrigerator until ready to use.
Shred chicken and cheese, set aside.Sprinkle salt on top of garlic cloves and mince. Chop Onion. Heat large skillet over medium high heat, when hot add oil, onions and garlic saute until onions are soft, be careful not to burn the garlic. Add spinach by the handful, as it wilts continue to add the rest of the spinach. It will wilt pretty quickly. Remove from heat and cool a little bit.
In a large bowl combine the chicken and spinach mixture, add cheese, keeping back a little to top the enchiladas. Add a ladle of the sauce and combine.
Spray the bottom of your baking dish with non-stick spay. Put a ladle or 2 of sauce in the bottom of the dish.
To roll the enchiladas, dip the tortilla into the sauce, add the filling and roll. Put in backing dish, seam side down. Top with remaining sauce and cheese. Bake at 350 degrees for 20-25 minutes until cheese is melted and sauce is bubbling.
