If using dried peas, pour the black-eyed peas into a bowl and cover with fresh water. Leave to soak for at least 4 hours, preferably overnight.
Rinse and drain beans. Add beans and water in a pot with a lid and bring to a boil. The water should be about one inch higher than the beans. Once boiling, reduce to a simmer, tilting the lid slightly to allow steam to escape and leave to cook for about 40 minutes or until tender. Add more water, if necessary, until beans are tender.
Drain beans. To make the dressing, whisk together the mustard, lime juice, vinegar, salt and oil in a bowl.
In a large bowl, combine the beans, sun-dried tomatoes, and parsley. Pour some of the dressing over the beans (about half) and mix well. Add more dressing and/or sea salt to taste. This salad is delicious on its own or served over lettuce, arugula or spinach leaves. You can toss the greens with any leftover dressing, or with a little more olive oil.