First, soak the gelatine leaves in a small bowl filled with cold water and set aside.
Next, pour the cream into a small pan and turn the heat on (gentle heat).
Add the vanilla extract.
Add the sugar.
Add the instant coffee.
Add the rum.
Stir gently for a few minutes until the cream gets close to the simmer point (avoid boiling the cream).
If you have a thermometer, check that the cream reaches 90ºC (193ºF) and, at that point, remove the pan from the heat.
The pan has been removed from the heat.
Now, squeeze the gelatine leaves.
Add the gelatine leaves into the pan.
Stir for a couple of minutes or until the gelatine is completely dissolved.
Next, strain the cream into the jug.
Now, pour the cream into the glasses (I usually fill 4 glasses half way) and put the glasses in the fridge for about 4-6 hours so that the panna cotta has time to set.
Finally, when you want to eat your panna cotta, I suggest you dust it with some cocoa powder and that's it. Enjoy it!