To make granita, put coconut water into a tray in keep in the freezer and every 30 minutes, use fork to break the ice. Repeat the step until the coconut water become flaky crystal. Keep in freezer.
To make simple syrup, bring water, sugar and pandan leaf to boil. Remove from heat, let it cool down and keep in refrigerator.
Dice water chestnuts into small cubes 1cm x 1cm. Mix food coloring and water together and stir in diced water chestnuts. Let them sit for 5minutes. Mix tapioca and arrowroot flour together. Toss water chestnut with the flour until completely coated each piece.
Bring water to vigorously boil and put the coated water chestnuts. Cook until the chestnuts are float and turn translucent. Remove the chestnut with spider and transfer into ice water.
To serve, put ¼ cup of cooked chestnuts, ¼ cup of coconut cream, 2-3 tbs of syrup (depends on how sweet you like) in a serving bowl. Put coconut water granita on top and scraped young coconut flesh.