What is the main flavoring ingredient in a Pimm's Cup?

The main flavoring ingredient in a Pimm's Cup is Pimm's No. 1 liqueur. This herbal, gin-based liqueur is the foundation of the drink, providing its distinctive fruity and botanical flavors. Pimm's No. 1 features a blend of spices and fruits, which gives the cocktail its refreshing and complex taste profile.

While other ingredients, like lemonade or various fruits, complement Pimm's No. 1 and enhance the drink's overall flavor, they do not serve as the primary flavor source. The use of gin in Pimm's No. 1 contributes to its base but is not the main flavoring element. Vermouth, although a common cocktail ingredient, is not used in a traditional Pimm's Cup, thereby not contributing to its character. The liqueur not only distinguishes the Pimm's Cup from other cocktails but is essential to its identity and appeal.