Place cubed potatoes in a large pot and cover with salted water.

Bring to a boil over medium-high heat and cook for 10-15 minutes, or until fork-tender.

Drain the potatoes and allow them to cool completely to room temperature.

In a small mixing bowl, whisk together sour cream, mayonnaise, garlic powder, salt, and black pepper until smooth.

In a large serving bowl, combine the cooled potatoes, crumbled bacon, shredded cheddar cheese, and sliced green onions.

Pour the dressing over the potato mixture and toss gently to coat evenly.

Cover and refrigerate for at least 1 hour before serving to allow flavors to meld.