1 tablespoon sliced green onions (green tops only)
Preheat oven with pizza stone in center of oven to 500° F.
Slice potato into ⅛-inch thick slices. Place potatoes in shallow pan and cover with water. Bring to a simmer and cook until just tender. Drain and reserve.
Stretch or roll pizza dough into 12-inch round. Slide dough onto pizza stone. Cook until just beginning to brown, 3-5 minutes.
Remove pizza and stone from oven. Spread crème fraiche over dough. Sprinkle with ½ cup cheese. Evenly distribute bacon lardons over cheese. Arrange cooked potato slices over cheese in single layer, leaving some space between slices. Sprinkle with remaining ¼ cup cheese. Brush exposed edge of pizza crust with olive oil.
Return stone and pizza to oven, placing on rack 3-4 inches below broiler. Broil 2-3 minutes until cheese is bubbly and just starting to brown and pizza crust is well browned.
Remove from oven. Sprinkle with sliced green onions and serve.