1. In heavy pot, bring the stock to a boil. Add garlic, tomatoes, chopped onion, jalapeno, and oregano to the stocks. Simmer uncovered for 30 minutes.
2. Broil the sliced onions until soft and a little brown. Add broiled onions, chicken, lime juice to soup, and simmer till chicken is heated.
3. Place toasted tortilla strips in each bowl and pour soup over strips.