For the rice pudding, cook a thick porridge from rice, milk, salt and lemon zest and let cool. Cream butter, sugar and yolks and gradually add the cooled rice porridge, fold in snow.
Fill a well-buttered gratin dish with layers of rice, finely chopped apples and raisins, with rice as the last layer. Top with butter flakes and bake the rice casserole in a medium-hot oven for about 45 minutes.