Fiesta Casserole

In skillet, cook ground beef and onions until meat is brown and onions are tender. Drain off excess fat. Stir in taco seasoning mix and tomato sauce, simmer for 5 minutes. Place 3 cups tortilla chips in 2 qt baking dish. Top with 1/2 grated cheese, the meat mixture, and then the remaining cheese. Top with additional 2 cups tortilla chips. Bake at 350 for 15 minutes. Garnish with sour cream and black olives if desired. Even stir in some jalapenos!!!