What is commonly added to a cocktail to enhance its flavor?

Bitters are commonly added to cocktails to enhance their flavor due to their concentrated mix of botanical ingredients, such as herbs, spices, and fruit. These complex flavors can add depth and balance to a cocktail, elevating the overall drinking experience. For example, a couple of dashes of aromatic bitters can refine the taste of a classic Old Fashioned, providing a nuanced flavor that complements the sweetness and alcohol.

The use of bitters is a staple in cocktail crafting, as they can amplify or contrast the primary flavors in a drink, allowing bartenders to create more sophisticated and finely-tuned beverages. They are often regarded as an essential ingredient in many classic cocktails.

Water, flavor syrup, and ice are also components that can affect cocktails, but they serve different purposes. Water is generally used to dilute drinks to adjust strength, flavor syrup adds sweetness but doesn't offer the same complexity as bitters, and ice is crucial for chilling drinks but does not enhance flavor directly.