Heat oil in a large soup pot over medium heat. Place chicken in the hot oil; cook, stirring only occasionally, until brown, about 10 minutes. Sprinkle fajita seasoning over the browned chicken and stir well to coat. Add the red and green bell pepper, poblano pepper, and onion to the seasoned chicken. Stir and cook over medium heat until the vegetables are soft, about 10 minutes.
Pour the fire roasted tomatoes, black beans, and chicken broth into the pot with the chicken and vegetables. Bring the soup to a boil over high heat, then reduce the heat to medium-low, and simmer uncovered for 30 minutes, stirring occasionally.
Season the soup with hot sauce, salt, and pepper to taste before serving.
