What additional ingredient is required for a Tall Iced Salted Caramel Mocha besides espresso shots?

To create a Tall Iced Salted Caramel Mocha, mocha sauce is indeed a vital component in addition to the espresso shots. Mocha sauce adds a rich chocolate flavor that complements the espresso and balances the sweetness from the salted caramel. It combines with milk, creating the creamy texture and delightful taste that characterizes this beverage.

The other options do not provide the same essential flavor profile. Flan syrup is not a standard ingredient for this drink, and coffee base is typically used in blended beverages, which is not relevant in this context. Ice is needed to serve the drink iced but is not an additional ingredient in terms of flavor. Therefore, mocha sauce is the key ingredient that enhances the overall flavor experience of the Tall Iced Salted Caramel Mocha.