Add the sugar to a sauce pan on the stove on low-medium heat. Continuously stir the sugar around the pan. The sugar will clump up before it completely melts.
Once the sugar melts, it will be a smooth amber colored liquid. It can take anywhere from 8-12 minutes, depending on your stove, to completely melt.
Add the butter - it will bubble up. Whisk until the butter and sugar are combined. Let the mixture sit and bubble for 30 seconds to one minute without stirring.
Add in the heavy cream. The mixture will bubble up. Whisk until the heavy cream is combined. Allow the mixture to boil for 30 seconds to one minute without stirring.
Remove from the heat and add the vanilla extract and salt and whisk to combine. Pour it into a bowl and let it cool. It will thicken as it cools.
Store in an airtight container in the fridge for 1 month or freezer for 3 months. The caramel will solidify in the fridge - microwave it to get it to the desired consistency when ready to use.