E-Z Enchilada Pie

1 pound lean ground beef
1 small onion, chopped
1 8-ounce can tomato sauce
1 1-1/4 ounce package taco seasoning mix
1 10-3/4 ounce can condensed cream of chicken soup
1/2 cup skim milk
12 6-inch corn tortillas
8 ounces shredded cheddar cheese (2 cups)

In a large skillet, brown lean ground beef and onion; drain off excess fat. Stir in the tomato sauce and taco seasoning. Bring the mixture to a boil. Reduce heat and simmer, uncovered, for 5 minutes. Remove the skillet from the heat.

Stir together the condensed soup and milk. Spoon half the soup mixture into a 13-by 9-by 2-inch pan. Cut the tortillas in half. Use 12 halves to place over soup in pan. Spoon meat mixture over tortillas. Top with remaining tortillas. Spoon remaining soup mixture over the tortillas. Top with cheese.

Bake casserole in 350-degree oven for 30 minutes or until heated through.