In a tall saucepan combine sugar, water, and apple cider vinegar. Stir to combine then place on stove over medium heat. Do not stir after this.
Place lid on the pan and bring the sugar mixture to a boil over medium heat. You can swirl the pan gently while the mixture is cooking to make sure there are no hotspots.
Cook on medium heat for approximately 5 minutes. Remove the lid and swirl the pan to make sure it is cooking evenly. The mixture will start to thicken.
Continue to cook until the sugar mixture begins turning a golden honey color. Keep a watchful eye to not let it get too dark or burn as this happens quickly at this stage.
Once the mixture turns an amber color (this took 7½ minutes from the start of the boil time for me) take off of heat immediately.
With whisk ready, add room temperature butter one tablespoon at a time whisking vigorously after each addition. The mixture will bubble and steam considerably so use caution while whisking.
After all the butter is added, continue whisking quickly as you slowly drizzle the room temperature heavy cream.
After the cream is added, place the caramel back on the stove over medium heat and bring to a boil. Boil for one minute, remove from heat and turn off the stove.
Add vanilla bean paste, salt, and alcohol (if using) and stir with either the whisk or wooden spatula to combine.
Allow the caramel to cool for 5-10 minutes before pouring into glass jar. It will be very runny when it is hot and will thicken as it cools.
Store in a covered jar in the fridge for up to a month.
Enjoy!