Prepare the Potatoes: Begin by placing the whole scrubbed potatoes in a large pot of salted water. Bring to a boil and cook until tender but still firm, about 20-25 minutes. Drain and let them cool slightly before slicing them into thick rounds.

Cook the Bacon and Onions: In a large skillet over medium heat, melt the butter. Add the sliced smoked bacon and cook until crispy, about 5-7 minutes. In the same skillet, add the thinly sliced onion and diced garlic, cooking until soft and translucent, about 5 minutes.

Deglaze with Wine: Pour the dry white wine into the skillet with the onions and garlic. Allow it to simmer for a few minutes, scraping up any browned bits from the bottom of the pan. This will infuse the dish with rich flavor.

Combine Ingredients: In a large bowl, combine the sliced potatoes, cooked bacon, onion and garlic mixture, sour cream or crème fraîche, chopped chives, salt, and pepper.

Assemble the Casserole: Preheat your oven to 375°F (190°C). In a greased baking dish, layer half of the potato mixture evenly across the bottom. Place half of the sliced Reblochon or Brie cheese on top. Add the remaining potato mixture, finishing with the rest of the cheese slices on top.

Bake: Bake in the preheated oven for 25-30 minutes, or until the cheese is bubbling and golden. Allow it to sit for a few minutes before serving, letting the flavors combine beautifully.

Serve: Scoop generous portions of this cheesy, comforting casserole onto plates, garnished with extra chopped chives if desired. Enjoy it alongside a crisp salad or a slice of crusty bread for a well-rounded meal.