Season chicken with garlic powder, oregano, cumin and salt and place in the bottom of the slow cooker. Cover with salsa verde, cover and cook HIGH 2 hours. 

Pre heat oven to 350°

Remove and shred chicken when done.

(Optional) if using corn tortillas heat oil in a small pan. once hot fry 1-2 mins a side. You don't want them too crispy as you'll need to roll them.

Place enchiladas in a greased baking dish and pour remaining green sauce over them and top with shredded cheese. Bake at 350 15-20 mins