- 1 cup (light packed) dark brown sugar
- 1 cup heavy cream
- 1/2 cup (1 stick) unsalted butter
- 1/4 cup Scotch
- 2 tablespoons light corn syrup
- 1 teaspoon vanilla extract
- 1 1/2 teaspoons flaky sea salt
- Cook brown sugar, cream, butter, Scotch, corn syrup, vanilla, and 1/4 cup water in a large saucepan over low heat, stirring, until sugar is dissolved. Increase heat to medium and bring to a boil (without stirring). Cook, swirling often, until sauce is thick enough to coat spoon, 8–10 minutes. Remove from heat and stir in sea salt.
- Sauce can be made 1 week ahead. Cover and chill. Reheat gently before using.