Peel, core, and slice the apples.
Take two mixing bowls and divide the egg yolks from the whites.
Soften the butter slightly in the microwave and let it cool down; then add it to the egg yolks and the sugar.
Stir all the ingredients until well combined.
Sift together the flour, cornstarch, and baking powder. Add it to the egg mixture, a little at a time.
Soak the raisins in rum and let them sit for 10 minutes then drain the raisins and lightly coat them with flour.
Whip the whites to a stiff peak with a hand mixer at high speed.
Fold the whites into the batter with downwards motions to maintain as much volume as possible.
Finely grate some of the apples into the batter and add the raisins.
Transfer the batter to a parchment-lined pan; the cake won’t stick to the pan so you can remove it easily.
Slice the remaining apples and arrange them on the top of the batter.
Sprinkle it with raw cane sugar for a crunchy delicious crust.
Pre-heat the oven to 350°F (180°C) and bake for 40 minutes in a static oven.
If the top gets too brown, lower the oven temperature to 325°F (160°C).
Do the toothpick test. Insert it into the cake, and if it comes out clean, it is ready.
Turn off the oven, and leave the cake in for about 5-7 minutes to cool down gradually; then open the oven door and let it stand for about 10 minutes more.
Let it cool and remember that if you baked it the day before, the taste will become more intense.