In a small bowl, sprinkle the gelatin over the water and let bloom for 5 minutes. Set aside.
In a saucepan, gently heat the coconut milk and sugar, stirring until the sugar has fully dissolved.
Add the gelatin mixture and whisk until fully dissolved.
Add the milk and rum and stir to combine.
To facilitate unmoulding, rinse eight 1/2-cup (125 ml) ramekins under cold water just before filling. Add the pannacotta mixture to the chilled ramekins. Let cool to room temperature. Cover the ramekins to prevent drying and refrigerate for
4 hours or until set.
Unmould the pannacotta and serve with Grilled Pineapple with Coconut Milk.