1 gala apple (or pink lady or golden) however only for decoration
1 tablespoon sugar
1 lemon
PROCEDURE
Separate the egg whites from the yolks and whisk them together with the cream of tartar. Sift the flour with the baking powder.
Peel the Renetta apples. Cut two into pieces and moisten them with rum. Slice the third and moisten it with a little lemon juice and cook it with a spoonful of water and one of sugar.
Beat the egg yolks with a whisk and add the water and oil until the mixture is frothy. Add the flour with the yeast, sugar and egg whites with movements from the bottom upwards so as not to deflate them. Add the apple pieces (if you prefer, reduce them to a puree).
Spread the cooked Rennet apple on the bottom of the chiffon cake mold. Pour the mixture into the mold and bake in a preheated oven at 160° for about 60 minutes (do the toothpick test, it could take 10 minutes more, depending on the power of your oven). Once baked, turn the chiffon cake mold upside down, resting on its feet.
Once completely cooled and unmolded you can cover the surface with the apple (optional) not peeled, sliced and caramelized in a pan with a drop of water and sugar; this step is not necessary, it has a purely decorative purpose and an extra apple does not hurt!!
If you don't have a chiffon cake pan, use a donut pan, it will be just as good, just a little less fluffy.