Combine the heavy cream and vanilla extract in a container (preferably with a spout). Set aside.
In a saucepan, pour the water and the sugar. Give a little stir. Put the saucepan over medium heat until it has a deep amber color, around 6-8 minutes. If using a thermometer, the temperature of the sugar should be at around 175 to 190 Celcius (345 to 375 F). It is important not to stir because it can make the sugar crystallize.
Remove the saucepan from heat and pour the cream into the saucepan in a slow, steady stream while stirring the caramel constantly with a wooden spatula.
Add a pinch of sea salt and stir. Leave the salted caramel to cool and transfer into a sterilized jar – it will keep in the fridge for up to two weeks.
(Note 1) Easily double the recipe if you need more quantities.