Chop cooled, cooked chicken meat into largish chunks. Tear tortillas into 1-inch wide strips.
In a large baking dish, alternate layers of tortillas, chicken meat and cheese (reserve 1/2 cup of cheese for topping) until all the chicken is used. Combine the remaining ingredients and pour over the layered mixture. Top with reserved cheese.
Cover with plastic wrap, then seal with aluminum foil.
To freeze: flash freeze casserole, then place frozen, covered dish into jumbo freezer bag.
To prepare: thaw casserole before baking. Remove plastic wrap, then replace foil. Bake covered casserole at 350-degrees until hot and bubbly. You may remove aluminum foil 10 minutes before taking the casserole out of the oven to melt cheese.
Allow to stand 5 to 10 minutes, then cut with spatula and serve.