How to make
Peel the apples and cut them into cubes. Beat the egg whites with a pinch of salt into snow. Beat the egg yolks with sugar until whitened, then add the oil.
Gradually, add a little bit of the snowy egg white, stirring with a spatula. Add the flour and baking powder in small portions and gently stir until it absorbs the entire amount to obtain a homogeneous mixture.
In a cake form with a diameter of 10″ (26 cm), place baking paper, then smear it with soft butter, add the sliced apples, sprinkle with cinnamon and pour the egg mixture on top.
Flatten the top and place in a preheated 360°F (180 °C) oven for 40 minutes. While it's baking, melt the butter and sugar on low heat, then add the walnuts. Remove the cake from the oven and while still hot, pour the butter mixture all over it with a spoon.
Return the cake to the oven and turn it off. Leave it in the oven for 30 minutes. Remove and allow it to completely cool before cutting.
