Bring water with sago to a boil. Stir until water boils. Turn off the heat and close the pot for 10 minutes until sago is transparent. Rinse sago under running tap water to remove all traces of starch. Drain and put aside.
Combine 700ml water, sugar, agar-agar powder, cocoa powder and instant coffee granules in a pot. Bring to a boil until agar-agar power and sugar are dissolved.
Remove a third of the agar-agar mixture and add evaporated milk, coconut milk and salt to this portion. Stir to mix well.
To the remaining two-thirds of the agar-agar mixture, add sago and stir well to combine.
Pour this mixture into a wet mould to three-quarters full. Set aside.
Once the jelly starts to set, use a fork to scratch the surface lightly. Use a spoon to fill up the jelly mould with the other portion of the jelly. Leave the jelly mould aside to set completely.