Put the chopped potatoes in a pot and cover with water. (I usually add about 1/2 teaspoon salt to water). Bring to a boil on top of the stove and cook about 10 minutes or until they are tender when you stick them with a fork. Drain and set aside.
Cook the bacon until crisp remove from skillet, drain and set aside. Add the chopped onion to the bacon drippings left in the skillet. Cook until tender. Stir in vinegar, water, sugar, salt, pepper and mustard. Bring to a boil.
Slowly add drained potatoes to the skillet along with half the bacon, crumbled. Turn down stove to medium and heat all the ingredients about five minutes stirring to mix.
Remove from stove and sprinkle on the rest of the bacon, crumbled, along with the parsley. I chopped up a few green onions for color on top, too. Add more salt and pepper if needed.