In a large stock pot or sauce pan, melt the butter until foaming. Add the diced onions and sauté till translucent, about five minutes. Add the garlic and stir for about a minute being careful not to burn.
Sprinkle in the flour and cook for a minute or two forming a lose paste. Add the stock, green chilies, cumin, oregano, salt and bay leaves. Bring to a simmer and keep simmering for about 10 minutes.
Remove from the heat, stir in the cream and allow to cool for about 30 minutes. Remove the bay leaves and puree with an immersion blender or in a regular blender.
NOTE: Sauce can be frozen per note.
Pre-heat oven to 350 degrees.
Combine the chicken, 3 cups of cheese, spices and sauce in a large bowl.
Spread a half cup of sauce into a large casserole dish. Fill each tortilla with about a ½ c. of the filling, role tightly, and place in the pan seem side down. Repeat with the remaining tortillas. If you have a smaller dish, you may need to use a second one.
Once all the enchiladas are filled pour the remaining sauce over the top and sprinkle with the remaining cup of cheese.
Cover tightly with foil and bake for 25 minutes. Remove the foil and place back in the oven for 5 - 10 more minutes until the cheese on top is bubbly and starting to brown.
Remove and let set for 10 minutes then serve.