Take a bowl and seive maida,baking powder,baking soda,salt.sift dry ingredients 3 times to get sponge cake. Separate egg yolks and egg whites.in a bowl add all egg yolk and mix it well.then add vanilla essence and mix it.then add milk and oil again give a nice mix.then add 1/2 of sifted flour into beaten egg mixture and gently fold using spatula.add remaining flour and fold it nicely.in another bowl add all egg whites beat it then add sugar little by little till it become fluffy.