First of all seive refined flour, baking powder and baking soda..mix icing sugar,melted butter, vanilla essence, lemon juice and curd..make a smooth batter..u can add little quantity of milk if required..Divide the dough into two sections and mix cocoa powder in one part of batter and other will be plain white

Take a Clean rectangular shape container..Set a butter paper on the bottom,spread the mixture and make two cakes white and brown one by one or make a partition in the center by placing a strip (shown in the image) and make white and choco cake at a time

Flatten the dough on a pastery board by spreading butter paper on it..Make a 1/4inch thick rectangle shape "roti" out of it.. Wrap up the roti around the checker board design Cake and keep it in the fridge for at least 2 hours to set completely..Take out of fridge, make marks on the top of bread loaf shape cake with the help of a knife and dust cocoa powder with the help of a sieve, cut 1/2inch thick slices