This bright, crunchy salad is a fresh and speedy way to follow the southern tradition of eating black-eyed peas on New Year's Day for good luck.
Soak onion in vinegar for 10 minutes. In a medium bowl, combine black-eyed peas, celery, parsley, and onion-vinegar mixture. Toss with oil and season with salt and pepper to taste. Serve immediately or refrigerate in an airtight container for up to 2 days.