In a heavy bottom pan take milk and boil on high flame.when milk is boiling turn the flame low medium.take out 3 tblsp milk in a bowl and add custard powder mix well. Now add vanilla custard powder in boiling milk stir continuously make sure there is no lumps.cook it for 5-6 minutes when it become thick add sugar and cook for 10 minutes.then turn the flame off.let cool the milk.