Cook potatoes until tender; drain and cool.
In the meantime, in a large salad bowl, combine mayonnaise, sour cream, mustard, salt and pepper; mix well.
Cut potatoes into cubes.
Add to mayonnaise mixture and toss to coat.
Add remaining ingredients and mix well. Cover and refrigerate for at least 2 hours.
This recipe makes 16-20 servings. It’s also great for picnics, potlucks and outdoor entertaining.