Traditional Upper Austrian potato curd cheese spread: mashed floury potatoes blended with sour cream, butter, finely chopped onions, caraway, and chives, spread generously over dark farmhouse rye bread.
Peel the warm boiled potatoes and mash them thoroughly with a potato masher or ricer into a mixing bowl until fine and lump-free. Allow to cool to room temperature.
Beat the softened butter and thick sour cream into the mashed potatoes with a wooden spoon until a smooth, spreadable, creamy texture is achieved.
Fold in the finely minced onion, ground caraway, sweet paprika, salt, and black pepper. Stir in half of the snipped chives.
Transfer the Erdäpfelkas to a stoneware serving dish. Scatter the top generously with the remaining fresh chives and serve alongside thick slices of dark Austrian sourdough rye bread.