In a food processor, chop red onion, celery stalks and 2 of the carrots. Cook mixture on on low-medium for 5 minutes. Slice additional 2 carrots. Add carrots and chopped red pepper and cook for an additional 5 minutes. Add additional olive oil if needed.
Add the 3 - 32 oz containers of chicken broth and bring to a boil.
As you are bringing the stock to a boil, cook the sausages, turning as needed, in a frying pan w/ a small amount of olive oil until fully cooked. Once the soup has risen to a boil, adjust to medium-low heat. Remove sausages from the frying pan and allow to slightly cool. Thinly slice sausages and add to soup.
Add sliced cremini mushrooms and zucchini to the frying pan. Cook on medium until fully cooked, stirring as needed. Add mushrooms and zucchini to the soup.
Add salt and pepper to taste. Reduce heat to simmer and simmer soup for 45 minutes
Warm basmati rice and potatoes in a microwave. Add a small portion of basmati rice and potatoes to a bowl and ladle soup on top. Garnish with cilantro, parsley and scallions.