First sieve maida and baking powder finely.

Mix butter with sugar and blend with a beater or by wooden spoon in a bowl.

Add maida and egg(beaten)alternately.

After that, divide the mixture into 2 equal halves.

To one half, add vanilla essence(dissolve vanilla in 2 tbsp milk) and mix well.

To the second half, add cocoa powder/chocolate (dissolve the cocoa in 2 tbsp milk) and mix well.

Grease a baking dish with butter and pour this mixtures alternately into it.

Stir the mix lightly with a fork.

Bake in a hot oven for about 45 mins.