Healthy Potato Salad

In 4-quart saucepan, combine potatoes, 1 teaspoon salt, and enough water to cover; heat to boiling on high. Reduce heat to medium-low; cover and simmer 10 minutes or until potatoes are just fork-tender.

Meanwhile, in large bowl, whisk buttermilk with mayonnaise, dill, vinegar, Dijon, green onions, 1/4 teaspoon salt, and 1/4 teaspoon coarsely ground black pepper.

Drain potatoes well. Toss hot potatoes with buttermilk mixture until coated. (Mixture will look very loose before chilling.) Cover and refrigerate potato salad at least 2 hours or overnight to blend flavors and cool slightly, stirring gently after 1 hour.