Open the vacuum sealed bag of Oleo Saccharum and pour in as much whiskey as will safely fit.
Carefully agitate the bag to incorporate the syrup into the whiskey.
Fine-strain the mixture over a large mixing container such as a punch bowl or drink dispenser.
Add the Chai Simple Syrup and lemon juice and stir well.
If you will serve later, put the mixture into the fridge and add 30% water. (Do not add ice when serving.) If you will serve immediately, add ice and serve.
(Optional) garnish each glass with a few shakes of Angostura Bitters to top with color.