red pepper flakes
salt and pepper to taste
Heat olive oil in a large saucepan over med-high heat. Add onions and saute, about 5 minutes. When onions are translucent, add garlic and saute 1 min. longer.
Add broth, tomatoes, potato, zucchini, oregano, red pepper flakes, and salt and pepper. Simmer over med-low heat for 20 minutes. Add chicken and heat 5-10 minutes longer.
Ladle soup into bowls. Top with shredded cheese, sliced avocado, tortilla chips, and fresh cilantro.