Simmer potatoes in salted water to cover until tender, 20 to 25 minutes, depending on size of potatoes. Drain; rinse with cold water to stop the cooking, and cool the potatoes. Peel, if desired, and cut into 3/4-inch chunks. In large bowl, combine sour cream, mayonnaise, mustard, salt, and pepper, mix well. Add potatoes, cheese, chives, and 1/4 cup of parsley, toss well. Stir in eggs, if desired. Cover and chill at least 2 hours or up to 8 hours before serving. To serve, sprinkle with the bacon and the reserved 2 tablespoons of parsley.