Vanilla is the second most expensive spice in the world. The vanilla bean grows on orchids which are native to Central America, but have since been introduced around the world, especially to Réunion and Madagascar. Though difficult to grow, it’s one of the most popular flavors in the world.Vanilla is rarely the star of a gin, it’s inclusion is often similar to its inclusion in baked goods. The flavor of vanilla often enhances the flavor of other ingredients. It’s also important not to confuse Vanilla the botanical, with Vanillin, the phenolic aldehyde which comes from aging spirits such as gin in oak barrels.