Lightly rinse an 8-inch square baking dish or similar shallow dish with water. Do not dry it completely; the slight moisture helps release the set jelly later.
In a medium saucepan, whisk the water, agar-agar powder, and sugar together while the pan is still cool. Bring to a full boil over medium heat, whisking often so the agar does not settle on the bottom.
Once boiling, continue to boil for 2 minutes while whisking. Remove the pan from the heat, then stir in the pandan extract and optional green food coloring.
Pour the hot pandan mixture into the prepared dish. Let it cool at room temperature until firm, about 30 to 45 minutes, then refrigerate until fully chilled, about 1 hour.
Cut the chilled pandan jelly into small cubes, about 1/2 inch (1.25 cm).
In a large bowl, gently stir together the chilled media crema, sweetened condensed milk, and optional reserved coconut syrup until smooth. Fold in the drained young coconut strips and pandan jelly cubes.
Cover and refrigerate for at least 2 hours so the flavors meld and the dessert is thoroughly cold. Stir gently before serving and spoon into small bowls or cups.