Prepare pasta according to package directions; drain. Set aside. (Ideally, you'll want the pasta to finish cooking when the sauce is ready.)
Saute peppers in olive oil for about 3 minutes. Add onion; saute 2-3 minutes until onions are tender. Add garlic; saute for another minute. Remove from heat. Add chicken.
In separate bowl, stir together soup, milk and cajun spice. Add to pepper mixture and return to burner over medium heat. Bring to a simmer. Remove from heat.
Add pasta to chicken mixture, toss together and serve.
Notes
Originally published October 24, 2014. Updated August 23, 2020.