Keep an eye on the pan: Just before the syrup turns medium amber, remove it from the heat (it will continue to cook for a few seconds). Once cooled, sauce can be refrigerated in an airtight container up to three weeks. Reheat in a saucepan or the microwave; stir in one tablespoon heavy cream.
- 1 cup sugar
- 3/4 cup heavy cream
- 1/2 teaspoon pure vanilla extract
- 1/8 teaspoon salt
Pour 1/2 cup water into a medium heavy-bottom saucepan; add sugar. Cook over medium heat, gently stirring occasionally, until sugar is dissolved.
Continue to cook, without stirring, until syrup comes to a boil, washing down sides of pan with a wet pastry brush two or three times to prevent crystals from forming. Let syrup boil, gently swirling pan occasionally, until it has almost turned medium amber.
Remove from heat, and carefully pour in cream (caramel will bubble). Add vanilla and salt, and stir with a clean wooden spoon until caramel is smooth.