Heat the grill. Coat 4 12” squares of heavy-duty foil with nonstick cooking spray.
Arrange the potatoes in the center of the foil and drizzle with the olive oil and sprinkle with the seasoning salt and garlic powder. Top with cheese and bacon. Wrap the foil around potatoes.
Grill, covered, over medium heat until the potatoes are tender (about 30 to 35 minutes).
Carefully open packets and sprinkle with green onions. Serve topped with sour cream.