I have a sponge cake recipe which has been in our family for a long time:
1.5 cups icing sugar
2.5 cups flour
1 cup milk
1 cup oil
1 tsp baking powder
cardamom and saffron
Separate the eggs. beat egg whites until soft peak and set aside. beat yolks and add sugar then mix well until creamy. add cardamom while mixing. Add oil and continue mixing. add lukewarm milk and mix for a few minutes until thoroughly mixed. Add yolk mixture to the egg whites and mix quickly for one or two minutes. then fold in the (flour+baking powder +saffron) mixture which is sifted into the egg mixture.
I was wondering how do we actually fold during the process of making the sponge cake. Do we fold it very lightly or fold until all the flour is fully incorporated? whenever I fold it to fully incorporate it, the texture does not get too airy and the volume decreases. or do I fold it lightly to ensure maximum air volume but whenever I pour the batter into the mould, I see remnants of unincorporated flour. Also is it correct to use electric mixer to mix egg white mixture and egg yolk mixture, or do I need to fold one into the other?