How to cook
Sift the flour with the baking powder. Beat the eggs with the sugar into fluffy cream and pour in the oil in a thin trickle while stirring nonstop.
Add the vanilla, a pinch of nutmeg and the flour in lots. Once it homogenizes, add the walnuts if you intend to use any.
Peel the quinces and cut them quickly into crescents, so they don't darken.
In a tray, laid out with baking paper and lightly greased, arrange a layer of quinces, pour in half of the cake mixture, arrange another layer of quinces and the remaining cake mixture.
Bake the cake in a preheated 356°F (180 °C) oven until it's dry on the inside. Then cool it and sprinkle with powdered sugar.