In a small heavy-bottomed saucepan, stir together sugarand 1⁄4 cup (60 grams) water until moistened. Cook over highheat, swirling pan occasionally but not stirring, until caramelturns a deep amber color and a candy thermometer registers355°F (180°C) to 360°F (182°C), 10 to 12 minutes.2. Remove from heat. Carefully whisk in cream until wellcombined. Whisk in butter until melted and well combined.Whisk in vanilla and salt. Let cool completely before serving.Refrigerate in an airtight container for up to 2 weeks.