In a large saucepan bring chicken stock to a boil. Reduce heat to a simmer and add chicken quarters. Simmer for 30 minutes.
Remove chicken quarters from pan and cool.
Add carrots, onions and celery to broth and continue to simmer.
Remove chicken meat from bones and add to broth mixture. Add herbs, garlic salt and pepper. Add orzo and cook until orzo is tender. Adjust seasonings to taste. Serve