A cold pasta salad is a chilled side dish that features pasta as the main ingredient, usually accompanied by various vegetables or pickled items like diced bell peppers, onion, celery, tomatoes, olives, banana peppers, and more. The ingredients in cold pasta salad are brought together with an oil, vinegar, or mayo-based dressing. Combining the ingredients together and then letting them rest for at least four hours allows the pasta absorb the flavors of the dressing and results in a flavorful salad.