How to cook
Beat the egg whites with the vanilla sugar into snow, then gradually add the yolks, yoghurt and oil. Add the flour with the baking powder, while stirring nonstop with a stirrer until you get a homogeneous mixture.
Pour 1/2 of the mixture into an 8 3/4″ (22 cm) diameter cake form (buttered and laid out with baking paper). Bake in a preheated 360°F (180 °C) oven for about 15 min. Take it out and sprinkle grated apples on top.
Sprinkle the ground walnuts and pour on the other half of the mixture. Return to the oven and bake until ready. Once the pie is nearly cooled, pour the glaze over it - made from the butter, powdered sugar, cocoa and milk brought to a boil.