Mexican Chef's Sald

1 head lettuce
1 large onion, chopped
4 large ripe tomatoes, peeled and chopped
4 ounces Cheddar cheese, freshly grated
1 (8 ounce) bag tortilla chips, crushed
1 pound ground beef
1 (15 ounce) can red kidney beans
1 cup Thousand Island dressing,
    mixed with Tabasco