2Sauté onions & pepper in hot oil in a large skillet over medium-high heat until tender.
Add garlic and sauté.
Stir in soup and next 4 ingredients; remove from heat.
3Spread 1 cup soup mixture in a lightly greased 13- x 9-inch baking dish.
Sprinkle with romaine.
Arrange tortillas, slightly overlapping, over soup mixture; top with chicken, Cheddar/Jack cheeses, romaine and soup mixture.
Repeat layers once.
Top with remaining tortillas, soup mixture, and cheeses.
4Bake at 350° for 40 to 45 minutes or until bubbly and golden.
Remove from oven let stand 15 minutes before serving.