Pour the water into a small bowl and sprinkle with powdered gelatine. Let for a few minutes to fully soak up the water.
Prepare the ramekins by greasing them lightly with some coconut oil and place them on a small tray.
In the meantime, heat up the coconut milk, sugar, salt and lime zest in a medium-sized saucepan until the sugar is dissolved, but don't let it come to a boil. Remove from the heat and add vanilla extract and the bloomed gelatine.
Stir the mixture with the whisk until the gelatine completely dissolves. If needed, return the mixture to low heat.
Pour the panna cotta mixture into the prepared ramekins and refrigerate for a minimum of 5 hours, preferably overnight. Use a fine-mesh sieve to ensure the silkiest texture.
Serve in a ramekin, or unmold to a plate by dipping the ramekin halfway through in a bowl filled with hot water. Leave it like that for 10-15 seconds, remove from the bowl, put the plate on top and turn it upside down. Give it a little shake to let loose. Return to water if it's not sliding out or run the knife around the edges.
Serve with fresh fruit such as passionfruit, pineapple, kiwis, strawberries macerated with some sugar (to let the juices), fruit sauces or coulis... the options are endless! :)
If you still don’t own one, I advise you to buy a kitchen scale – they’re cheap and easy to use, and always guarantee the same results in baking.