In a medium saucepan set over medium-high heat, combine the sugar with 1/4 cup cold water and stir to combine. Cook, without stirring, until the sugar has turned a deep amber hue, approximately 10 to 12 minutes.

Meanwhile, warm the cream in a small saucepan. When the caramel is ready, slowly, Wisk in the warm cream and continue simmering the mixture until it is smooth, another 2 to 3 minutes. Remove from heat, then whisk in the butter, and then the salt, to taste. Serve warm.