Preheat oven to 425. Line a baking pan with parchment paper.
Brush both sides of the potato slices with oil and season with salt and pepper.
Roast until golden brown. This takes 25-30 minutes (or longer), depending on your oven and the thickness of the slices. Flip halfway through.
Sprinkle with cheese and bacon.
Bake for an additional 3 minutes to melt the cheese.
Top with sour cream and green onions.
Notes
Cook Time - The cook time on this can vary quite a bit. It's hard to slice potatoes exactly ⅓ inch thick. You want them to be golden brown and crispy. I suggest giving yourself some extra time the first time you make them.