Combine sugar and water in a saucepan on medium heat. Without stirring let the sugar and water bubble until it turns a dark amber. Roughly 20 minutes.
When the mixture is a deep amber reduce heat to low. Slowly add cream, stirring slowly. It will thicken up but just keep stirring until it turns into a caramel.
Scrape in the vanilla paste, lemon juice, salt, butter, and bourbon. Stir to combine.
