Bring a large pot of lightly salted water to a boil; add pasta and cook, stirring occasionally, until tender yet firm to the bite, about 11 minutes. Drain.
Heat oil in a large saucepan over medium heat; add orange bell pepper, red bell pepper, celery, carrots, and garlic. Cook and stir until slightly tender, about 5 minutes.
Pour tomato soup plus 1/2 can water into saucepan. Add potatoes, chicken broth, basil, onion powder, salt, and pepper; stir to combine. Bring to a boil; reduce heat and simmer until flavors combine, about 1 hour. Serve over cooked pasta.