Preheat oven to 375 degrees F. Grease a large baking sheet with a tablespoon of olive oil.
Slice the potatoes into ¼ inch thick slices, using a mandoline or knife, and spread the slices in a single layer on the prepared baking sheet. Brush lightly with additional olive oil and sprinkle with salt and pepper to taste.
Bake potato slices for 20-25 minutes until lightly golden and tender.
Turn the broiler on. Sprinkle grated cheese evenly on the potato slices and broil for a minute or two, until cheese is melted and bubbly.
Let potatoes cool for 5-10 minutes on the baking sheet and remove to a serving platter with a spatula. They may stick a little, but should come off pretty easily.
Top with a dollop of sour cream, a little bacon and a sprinkle of green onions.