Herbal liqueurs such as Chartreuse and Bénédictine are classic digestifs and are also good in cocktails, such as the Singapore Sling. The flavour of herbal liqueurs varies a great deal, so if a cocktail recipe calls for a particular liqueur, it’s best to stick to that specific drink.
For example, Strega should not be used as a substitute for Galliano in cocktail recipes but the two can be used interchangeably in cakes and desserts, although the final flavour will differ.