Muddling helps to release the flavors of the fresh ingredients so that they bind with the alcohol better. However, one must take care not to over-muddle when working with delicate herbs such as mint and basil. This can impart a bitter taste in the drink. Instead, use a light hand and tap them a few times with the muddler. Use a heavier hand with rosemary, lime, and other firmer ingredients.
Muddlers come in either wood, bamboo, stone, or metal. Our muddler, pictured above, is a Rosle Fruit Muddler/Caipirinha Pestle. We like it because it's easy to clean, fits in the hand well, and the raised tips and wide base are more efficient at muddling fruit. Yet, it's good for delicate herbs, too.
(Images: Kathryn Hill)