In the Earls signature caesar, what is the main mixer used?

The correct answer is Clamato. In the context of the Earls signature Caesar, Clamato serves as a key ingredient that combines tomato and clam juices, providing a distinct flavor profile that characterizes this classic cocktail. The use of Clamato enhances the drink with umami and savory notes, which are essential for the traditional Caesar experience.

While the other options like passion fruit, pineapple, and grapefruit might add interesting flavors to cocktails, they are not typically associated with a classic Caesar. The Caesar cocktail relies heavily on the unique flavor of Clamato, making it integral to the drink's identity at Earls.