In a large pot, boil potatoes in salted water until tender; drain.
Cook diced bacon in a skillet until crisp, then drain on paper towels.
In a large bowl, combine sour cream, mayonnaise and pepper. Add potatoes, bacon, cheese and green onions, reserving a bit of cheese, onions and bacon to garnish the top of the potato salad.
Top with reserved cheese, onions and bacon before serving.
Serve while warm or serve chilled.