In abowl mix eggs and sugar

Add oil and milk and continue beating till well blended add vanilla essence

In a separate bowl add flour and baking powder

Gradually add the flour mixture to the wet ingredients and beat just until the batter is smooth and all the dry ingredients are incorporated

The batter consistency should be medium, not too thick not too runny

Divide the mixture into 2 equal portions, add cocoa to one leave the other plain

Pre heat oven @ 180 degrees

Mix the batter and make a swirl