Heat olive oil in large pot or cast iron skillet. Add onion and sauté until translucent. Add garlic and sauté slightly without browning.
1 ½ tablespoon olive or vegetable oil, ¾ cups yellow onion, 1-2 clove garlic
Add chicken, tomatoes, stock, cumin and oregano. Bring to a boil and then reduced to simmer. Continue cooking until chicken is done.
½ pound boneless skinless chicken breast, 1 can 14-15 ounce diced tomatoes, 16 ounce chicken stock, 1 ½ teaspoon ground cumin, ½ teaspoon dried oregano
While soup is cooking, cut tortillas into ½-inch strips. Heat ½ inch oil in a skillet until a test tortilla strip sizzles when dropped into oil. Fry tortilla strips one layer at a time. Watch carefully so not to burn. Remove with tongs and drain on paper towels. Repeat until all are fried.
4-6 small corn tortillas, oil for frying
To serve: place fried tortillas in bottom of serving bowls. Pour in soup and garnish with grated cheese and a few sprigs of cilantro.