Preheat oven to 375.
Place chicken breasts in a large mixing bowl and season with garlic powder, chili powder, salt, pepper, parsley and olive oil; mix until well combined.
Transfer chicken breasts to a baking dish in one layer.
Bake for 35 to 40 minutes, or until thoroughly cooked.
In the meantime, work on the soup.
Heat olive oil and butter in large soup pot over medium-low heat.
Add onions, carrots and parsley, and season with salt and pepper.
Cook for 6 to 8 minutes, or until vegetables are tender, stirring frequently.
Stir in peppers and garlic and continue to cook for another 5 minutes, or until peppers are tender.
Take out the cooked chicken and cut it into cubes.
Transfer chicken cubes to the soup pot.
Stir in tomatoes and black beans and season with chili powder, paprika, and cumin.
Add chicken stock and bring to a boil over medium-high heat.
Turn down to a simmer and continue to cook for an additional 10 minutes.
Taste for salt and pepper; adjust accordingly.
Garnish with tortilla chips and avocado slices.