In a medium saucepan, combine the coconut milk, heavy cream, and sugar. Heat the mixture over medium heat, stirring until the sugar dissolves. Make sure the mixture warms up but does not boil.

In a small bowl, sprinkle the gelatin over 2 tablespoons cold water. Let it sit for about 5 minutes. The gelatin will soften and get spongy.

Take the warm cream mixture off the heat. Stir in the vanilla extract and rum extract. Whisk in the bloomed gelatin until it’s completely dissolved. To remove any lumps, strain the mixture through a fine sieve.

Lightly grease some ramekins or molds. Divide the panna cotta mixture evenly among them. Place the ramekins in the refrigerator for at least 4 hours, or overnight, until they are fully set.

In another saucepan, combine the diced pineapple, pineapple juice, brown sugar, and lime zest over medium heat. Cook until the pineapple starts to soften and the sugar turns into a syrup. Stir in the cornstarch mixture and cook for one more minute until the sauce thickens. Allow the sauce to cool completely.

To serve, run a knife around the edge of each panna cotta. Invert the ramekins onto plates. Spoon the pineapple sauce over the top and garnish with toasted coconut flakes and a sprinkle of fresh lime zest.