PREPARE THE INGREDIENTS

1. Place the granulated sugar in a medium-sized stainless steel saucepan (avoid using a dark-colored or nonstick pan).
2. Measure out the butter, heavy cream, vanilla extract, and salt and set aside. Have a heat-safe rubber spatula and a wire whisk ready.

MAKE THE CARAMEL SAUCE

1. Place the saucepan over medium heat. Stir the sugar occasionally with a rubber spatula as it begins to heat and clump. Once clumps form, stir constantly until the sugar starts to melt. When most of the sugar has liquefied, switch to a wire whisk and continue stirring until the sugar is fully melted and reaches a deep amber color.
2. Remove the saucepan from the heat and carefully add the cubed butter. Whisk until the butter is fully melted and incorporated, about 30 seconds. The mixture will bubble vigorously, so use caution.
3. Slowly pour in the warm heavy cream while whisking constantly. The caramel will bubble and steam again as the cream is added.
4. Whisk in the vanilla extract and salt until fully combined. Let the caramel cool in the saucepan for a few minutes, then transfer to a heat-safe jar or container and allow it to cool to room temperature.
5. Cover and refrigerate for up to 2 weeks. To reheat, microwave in 10-second increments, stirring between each, until smooth and pourable.