Boil the potatoes until done and cut them into equal pieces after they have cooled. Chop the shallots into rings that are not too thin. Mix the crème fraîche, the Marne Grove Mustard, the curry powder and the white wine vinegar in a bowl and stir in the (fresh) chives. Then stir the sliced ​​potatoes and shallots into the sauce until everything is evenly distributed. Let it rest so that the flavors can blend well. The salad is at its best when you let it rest in the refrigerator overnight.