Preheat oven to 350. In a 12x8 inch baking dish, place 3 tortillas. Layer on 1/3 of the tomatoes, chicken, scallions, chilies, olives sour cream and cheese.
Cover with 3 more tortillas. Repeat the layering process twice, ending with tomatoes and cheese.
Bake, uncovered, for about 35 minutes or until bubbly and heated through.