1: Bring a large pot of water seasoned with cajun seasoning to a boil. Cook the pasta according to the package, until al dente. Drain & rinse with cold water. Set Aside.
2: Finely dice the celery, onion, and bell pepper. Rinse the purple onion with cold water if desired. Add to a bowl.
3: Stir in the mayo, mustard, vinegar, and sugar. Season to taste.
4: Stir in the noodles and refrigerate for about thirty minutes before serving.
