Add the brown sugar, butter, salt and half a cup of cream to a small pot on the stove. Heat on medium high, stirring occasionally until the butter melts
Heat the mixture for 5 minutes without stirring before removing from heat and adding both the vanilla and stirring well. Cool in the fridge while the rest of the ice cream base is made
Add the remaining one and a half cups of cream and milk to a separate small pot on the stove. Gently heat until just warm and do not overheat or boil
Separate the egg yolks and beat them before slowly adding the milk and cream to mix in well
Transfer the egg mix to the top of a double boiler. Add the glucose syrup and stir well. Cook on medium low, stirring frequently for about 5-10 minutes or until mix thickens and coats the back of a spoon. Do not over heat or the eggs will scramble
Remove from heat and cool. Strain into the butterscotch and mix well. Transfer to a heatproof container and chill in the fridge for at least 4 hours
For the bourbon butterscotch, add brown sugar, butter, salt and half a cup of cream to a small pot on the stove. Heat on medium high, stirring occasionally until the butter melts
Heat mixture for 5 minutes without stirring before removing from heat. Then add the vanilla, lemon juice and bourbon and stir well. Allow the mixture to cool until ready to churn ice cream
Put your storage container in the freezer to chill. If using a self refrigerating ice cream churner switch on about 10 minutes before churning, otherwise take the churning bowl out of the freezer right before churning
Churn the ice cream and layer it into the container, drizzling with bourbon swirl as you go. Cover and freeze for at least 4 hours before serving
Notes
The time listed is for cooking and churning time. Does not include cooling (10 minutes), chilling (4 hours) or freezing time (4 hours)