Try this delicious cake recipe:
Peel the cooked and cooled Jerusalem artichokes and cut into narrow slices or coarsely grate. Heat the fat in a large omelet pan, add the Jerusalem artichokes a little at a time, sprinkle with salt and cook until lightly yellow. Press the Jerusalem artichokes together with a roasting ladle to form a cake, spread 2 to 3 tbsp. water evenly over them, add fresh butter if desired. Cover the rösti and roast on a low fire until a yellow-brown crust has formed on the bottom. Turn the finished Rösti out onto a hot plate and bring to the table.