Cover codfish with cold water. Let stand several hours. Drain. Add potatoes. Cover with water. Cook until tender. Drain. Mash. Add cream, butter, and well-beaten egg yolks. Beat until light. Season to taste. Fold in stiffly beaten egg whites. Pour into hot frying pan containing the butter. Cook until brown on the bottom. Fold like an omelet. Serve at once. 8 servings.