Add the potatoes to a large stock pot and fill with cold water until the potatoes are just covered. Add 2 tablespoons kosher salt to the water and bring to a boil over high heat. Turn the heat to low and simmer for 20 minutes or until the potatoes are cooked. Drain.

Transfer the potatoes to a large bowl and sprinkle with the vinegar. Allow the potatoes to cool to room temperature.

Using a potato masher or a fork, mash the potatoes until they break down to smaller bite sized pieces. Don't over mash. Add the mayonnaise, mustard, eggs, scallions, pickles, dill, parsley, salt and pepper to the bowl. Carefully fold all the ingredients until well blended.

Cover and refrigerate for up to 48 hours. Serve sprinkled with additional dill, scallions and parsley if desired.