Place potatoes in a large pot and cover with water. Bring to a boil and simmer for about 15 minutes, or until tender. Drain well and let cool.
In a small bowl, stir together the buttermilk powder, garlic powder, onion powder, parsley, dill, chives, sea salt, sugar, black pepper, and mustard powder.
In a large bowl, combine sour cream, mayonnaise, and seasoning mix.
Add potatoes, cheddar cheese, and green onions and stir well.
Sprinkle bacon on top, or add to individual servings. Refrigerate until chilled.
Stored covered for up to 3 days.