Put one-half cup of cream into a small sauce pan and bring to a boil, when it comes to a good boil add the flour all at once, and stir smooth; cover and let cook on the edge of the stove five minutes, then remove; when cool add the eggs one at a time, stir the batter until the egg disappears and the batter is smooth; add the remaining egg and work it likewise into the batter; beat the batter well with the spoon that it may be perfectly smooth. Have the potato cut into one-half inch cubes, add the cold water, onion, and salt; and when the potato is nearly cooked through, drop in the batter by spoonfuls, scraping it off the spoon so it will drop in one piece into the boiling stew. Cover, and let cook about ten minutes. Have one tablespoon lightly browned flour and a bit of sage braided smooth in cold water, turn into stew, season with salt to taste. Celery salt may be added if desired; then add the nut cero which is cut in large cubes, and the remaining cream. Shake the sauce pan so as to mix well; let stand on the edge of the stove to draw for ten minutes; dish up on a platter, having a dumpling on top. Sprinkle over a little finely chopped parsley, and serve.