If a first class customer requests Vodka on the rocks, how should it be served?

Serving Vodka on the rocks typically involves pouring the spirit over ice to ensure it's well chilled while maintaining the desired dilution level. A cup with Vodka already poured over ice provides the immediate experience the customer expects—a refreshing drink served simply and efficiently.

While serving in a Highball glass could be appropriate, and some may argue for a specific garnish, the essence of serving Vodka on the rocks emphasizes straightforwardness and the cold temperature from the ice, which is best achieved with just the vodka and ice. Chilling without ice contradicts the request for "on the rocks," and serving without garnish doesn’t align with the expectations for the first-class experience, which often leans toward a more polished presentation. Therefore, the most fitting choice centers on delivering the drink as requested, amid the convenience and quality that first-class service aims to provide.