In a food processor / blender , blend 2 cups milk , cocoa , sugar, vanilla , salt .
In a heavy bottom pan bring this mixture to a simmer on a low medium heat stirring frequently.
In the meantime blend the rest ½ cups milk and corn flour .
Once the mixture in the pan starts simmering slowly pour in the corn flour mixture in the pan .
Stir until thickens and coats the back of the spoon .
The pudding thickens more after cooling and chilling.
Taste test and add sugar if needed.
Transfer the pudding in a glass bowl and let it cool on room temperature.
Cover it with cling wrap touching the pudding and place it in the refrigerator for at least 2 hours to chill or up to 3 days.
You may add cinnamon or some festive flavoring to your pudding. This is very rich chocolaty pudding. Adjust sugar to your taste if you like it sweeter. use 3 tablespoon cornflour if you want to serve pudding warm or like it thick and creamy. Use 4 tablespoon cornflour and 1/2 cup semi sweet chocolate chips if you want it set like panna cotta.