Preheat oven to 400°F.
Heat large pot of water to boiling. When at a full boil add the diced potatoes and parboil 5-7 minutes. (Or you could steam them for 5-7 minutes). Drain and set aside. (Can be made a day ahead and refrigerated.)
In a large skillet, cook bacon over medium high heat until it renders its fat and edges start to crisp, You are not looking to fully cook the bacon bits. (If you wan to lighten the dish somewhat you can drain off most of the bacon fat at this point).
Add the onions to the pan and cook 5-7 minutes until they are translucent. Add the butter and then the diced potatoes and cook another 5-7 minutes till potatoes begin to soften. Season with salt and pepper.
Add the wine and and cook another 5 minutes or so til wine is absorbed.
Remove skillet from the heat and stir in the crème fraîche.
Leave the rind on the cheese and chop in to ½" cubes.
Rub the inside of a 9 X 13" oven proof baking dish with the cut garlic. Add half the potato mixture to the casserole, sprinkle half the cheese evenly around, top with the remaining potato mixture and sprinkle the last of the cheese evenly over the top.
Bake ucovered 20-30 minutes until potatoes are tender, cheese is fully melted and top is beginning to brown.
Serve with fresh ground pepper, pickled onions and cornichons