Sauce:
cook onion, garlic, coriander, and pepper in butter until onion is tender. Stir flour into sour cream; add to onion mixture. Stir in broth and chili peppers all at once. Cook and stir until thickened and bubbly. Remove from heat, stir in 1/2 cup of cheese.
Filling:
stir 1/2 cup sauce into cooked chicken. place 1/4 cup filling atop each tortilla an droll up. Arrange rolls in 12x7.5x2 inch baking dish. Top with remaining sauce. Bake, uncovered, in a 350 degree preheated oven for 35 minutes or until heated through.
Sprinkle on remaining cheese and bake until melted. Top with olives. Let stand 10 minutes. Makes 4 servings.