1teaspoonsea saltstrongly recommend using Fleur de Sel
Instructions
Pour the sugar into a high-sided pot. Remove any noticeable impurities in the sugar.
Turn the heat to medium-high and allow the sugar to cook for 2 to 3 minutes, or until you see it starting to melt and caramelize. Using a wooden spoon or a whisk, stir the sugar.
Continue cooking and stirring until all of the sugar has melted and has become a dark rich amber color. If it is darkening too quickly, reduce the heat to medium.
Add in the butter and stir until it has melted. It will bubble and foam at first then settle back down.
While stirring, slowly pour in the heavy cream. The sauce will rapidly bubble and steam. Don't worry if the sugar seizes, just keep stirring until it all melts back together. Allow the caramel to bubble and cook for about 1 minute then remove from the heat.
Add in the vanilla and salt.
Pour the caramel into a heat-safe glass jar and allow it to cool before using.
Notes
Storing the caramel sauce once it's cooled:
In the fridge, the caramel will be good for about a month.
Caramel can be frozen for up to 3 months but it will need to be transferred to a plastic container so that it doesn't shatter.
On baked goods, the caramel will be ok at room temperature for 3 to 4 days.
Chilled caramel will become quite thick. To thin it back out, stir in a splash of cream or water.