1) Pre-heat the oven by setting it to a moderate temperature.
2) Take a bowl and cream shortening in it.
3) Add the egg yolks and sugar to it mixing well.
4) Add ½ of the milk to it.
5) Sift flour with baking powder and add ½ to the batter.
6) Add the milk, rest of flour and flavoring mixing them well.
7) Take two layer cake tins and grease them.
8) Place the tins in a pre-heated oven and bake for 20 minutes approximately.