In a small pot or very large saucepan, combine the potatoes with 1 quart of boiling water. Cover and bring to a boil again. Reduce the heat, and boil 9 to 14 minutes. Do not overcook. Cool in a colander under cold running water. Drain well.
Meanwhile, place the mayonnaise in a large serving bowl. Slowly add the buttermilk, whisking until smooth. Stir in the basil, thyme, marjoram, celery seed, salt (if desired), and hot pepper sauce. Stir in the cucumber and chives. Gently stir in the cooled and drained potatoes.
Serve warm, or cover and refrigerate 1 to 2 hours, or cool in the freezer for 15 to 20 minutes. Cover and refrigerate. Leftover salad will keep in the refrigerator for 3 to 4 days.