Place onion in a large pot with oil and sauté until golden.

Add vegetables and sauté an additional five to 10 minutes. Season with salt and pepper.

Add just enough water to cover vegetables and bring to a boil. Lower flame and simmer for about half an hour or until the vegetables are cooked through.

Blend vegetables with hand blender until smooth. Slowly add chicken soup to vegetable mixture until desired consistency is reached. Bring soup to boil. Add diced chicken to pot and cook through, about 15–20 minutes.