In a large soup pan, sauté the onion, garlic, and jalapeno together in the olive oil until the onions are tender. Add the canned green chilis, cumin, oregano, cayenne pepper and black pepper. Stir together and add the chicken broth. Bring to a boil, turn down to medium low, and simmer for 10 minutes. Add the chicken and cook for another 5 minutes. Serve with fresh cilantro and avocado. Enjoy!