In a small bowl, mix the cornstarch with a little bit of the orange juice (enough to dissolve the cornstarch completely) to create a slurry. This helps prevent lumps.

Pour the remaining orange juice into a saucepan and add the sugar. Bring to a simmer over medium heat, stirring until the sugar is completely dissolved.

Slowly whisk in the cornstarch slurry to the simmering juice.

Continue to cook, stirring constantly, until the mixture thickens and starts to bubble. This usually takes about 5-7 minutes.

Once thickened, pour the mixture into individual dessert bowls or a single serving dish. Allow to cool at room temperature for a few minutes, then place in the refrigerator to chill and set completely, usually about 2-3 hours.

Before serving, sprinkle grated coconut over the top of the dessert for added flavor and decoration if desired.