4 pounds Yukon Gold potatoes, peeled and cut into 1-inch dice
1/4 pound thickly sliced bacon, cut crosswise into strips
2 large onions, finely chopped
Freshly ground pepper
1/2 cup dry white wine
One chilled 5-ounce whole Reblochon or Pont-l'Évêque cheese, rind removed, cheese halved horizontally
Preheat the oven to 425°. In a large saucepan, cover the potatoes with water and bring to a boil. Salt the water and cook the potatoes until tender, about 12 minutes; drain well.
In a large skillet, cook the bacon over low heat, stirring, until crisp, about 7 minutes. Add the onions and cook, stirring occasionally, until softened, about 12 minutes. Add the potatoes, season with salt and pepper and toss to coat.
Place the 2 cheese halves on the bottom of a roasting pan and spoon the potatoes and onions on top. Pour the wine into the pan and bake for 12 minutes, or until the cheese has melted. Using 2 metal spatulas, gently stir the potatoes to coat with melted cheese, sprinkle with pepper and serve at once.