Beat the whites with a pinch of salt. When they are white, add the yolks and then the sugar and continue beating until you get a firm meringue.
In a bowl, add the flour and cocoa powder together with the baking powder or yeast.
Gradually add the flour to the merengue already prepared, making enveloping movements with the spoon.
Do not forget to add rum and vanilla.
Once you have the dough completely homogeneous, pour into the greased mold.
Place the mold in the pre-heated oven at 175º C and bake for 55 minutes. At 45 minutes it is convenient to open and move the mold a little to check that the cake does not "shake". If it is already firm at the top click to check that it is completely set inside. If the skewer comes out wet, leave more time and check again every 5 minutes.
Once it is completely done, remove the sponge cake from the oven.
