Combine whipping cream and sugar in a heavy saucepan.
Place over medium heat, and cook, stirring constantly, until sugar dissolves. Stir in chocolate, corn syrup, and butter. Cook over medium-low heat, stirring occasionally, until chocolate melts and all ingredients are blended.
Remove from heat; stir in vanilla and salt.
Let cool to room temperature.
Transfer sauce to jars with tight-fitting lids. Store in refrigerator. To serve, spoon sauce into a microwave-safe bowl, and microwave at HIGH for 20-second intervals or until pourable.
