Layering the tortillas rather than rolling the enchiladas make assembling this casserole a cinch. If you have the time, substituting roasted and chopped poblano peppers for the canned chiles adds another depth of flavor.
2 Tbsp butter
2/3 cup onion, diced
2 Tbsp all-purpose flour
1 1/2 cups chicken broth
8 oz chopped green chile peppers
1 clove garlic, minced
3/4 tsp salt
1/4 tsp ground cumin
12 6 inch corn tortillas
1 cup shredded Monterey Jack cheese
1 cup shredded Cheddar cheese
2 cups shredded, cooked chicken breast meat
1/2 cup heavy cream
1/2 cup reduced fat sour cream
1/4 cup sliced green onion
1. Prepare salsa verde: Melt butter in saucepan over medium heat. Sauté the onion until soft. Stir in the flour. Add the broth, then add the chiles, garlic, salt, and cumin. Simmer about 15 minutes to blend flavors, then set aside.
2. Preheat oven to 350°.
3. Combine the cheeses and keep 1/2 cup aside for topping.
4. Spoon a small amount, ( just enough to barely coat the bottom ), of the salsa into the bottom of an 8 or 9 inch baking dish. Line the bottom of the dish with 4 tortillas, cutting to fit. Add 1/2 of the chicken, followed by 1/2 of the cheese and then 1/2 of the salsa. Repeat the layers a second time, finishing with the last 4 tortillas.
5. Whisk together the cream and sour cream and spread over the last layer of tortillas, then sprinkle on the reserved cheese and sliced green onions.
6. Bake covered in preheated oven for 20 minutes, then uncovered for another 20, or until the cheese is melted. Let stand , covered, for 10 minutes before serving.