Place the cubed potatoes in a large pot and cover with cold water by 1 inch. Add 1 teaspoon of salt to the water.
Bring to a boil over high heat, then reduce heat to medium and simmer until potatoes are tender but still hold their shape, about 12-15 minutes.
Drain the potatoes thoroughly and transfer to a large mixing bowl. Let cool to room temperature.
While the potatoes cook, heat a skillet over medium heat. Add the turkey bacon slices and cook until crispy, about 5-7 minutes, flipping as needed.
Transfer cooked bacon to a paper towel-lined plate to drain. Once cooled, crumble into small pieces.
In a separate bowl, whisk together sour cream, mayonnaise, Dijon mustard, apple cider vinegar, granulated sugar, garlic powder, onion powder, salt, and black pepper until smooth and well combined.
Add the dressing to the cooled potatoes and gently fold to coat all the potatoes evenly.
Fold in the shredded cheddar cheese, crumbled turkey bacon, and chopped green onions, reserving a small amount of cheese and green onions for garnish if desired.
Taste and adjust seasoning with additional salt and pepper if needed.
Transfer the potato salad to a serving bowl and garnish with the reserved cheddar cheese and green onions.
Refrigerate for at least 1 hour before serving to allow flavors to meld. Serve chilled or at room temperature.