Preheat and oven to 200C
Slice the potatoes thinly (around 3mm) without cutting all the way through.
Place the potatoes on a baking sheet, stuff the sliced butter and garlic in between a few of the cuts in the potatoes and season with salt and pepper.
Roast in a preheated 200C oven until crispy on the top and tender in the middle, about 1 hour.
Meanwhile cook the bacon until crispy and crumble it.
Sprinkle the potatoes with the cheese and bacon and return to the oven until the cheese has melted, about 5 minutes.
Serve topped with sour cream, and green onions.
