Hydrate the agar-agar. In a small bowl, mix the agar-agar powder with the water and let it sit to hydrate.
Prepare the pandan leaves. Cut the pandan leaves into short pieces.
Blend the pandan. Blend the pandan leaves with the water until broken down and fragrant.
Strain the juice. Strain the mixture through a fine strainer or cheesecloth, pressing well to extract smooth pandan juice.
Heat the pandan juice. Pour the pandan juice into a pot over low-medium heat and bring it to a gentle simmer. Stir the soaked agar-agar once more to loosen it, then add it to the pot while stirring.
Dissolve the agar-agar. Stir continuously until the agar-agar is fully dissolved and the liquid looks clear. Run a spoon through the mixture, if you see any graininess, keep stirring until smooth.
Sweeten the mixture. Add the sugar and stir until completely dissolved.
Pour and set the pandan layer. Pour the pandan layer into your mold or cups. Let it set at room temperature until just firm (about 30 minutes) before adding the coconut layer on top. Meanwhile, prepare the coconut layer.