Place potatoes and water to cover in a large Dutch oven; bring to a boil over medium-high heat. Cook 25 minutes or until potatoes are tender. Drain and let cool. Cut into 1/2-inch-thick slices.
Stir together sour cream and next 4 ingredients.
Stir together potatoes, sour cream mixture, green onions, and parsley in a large bowl. Cover and chill 1 hour or until ready to serve. Stir in bacon just before serving.