Fresh herbs can be delicate, and it's not always easy to figure out how to cut, crush, or muddle them to make the most of their flavors. Get too rough, and you have a bunch of bruised and muddy-tasting herbs, which is due to too much chlorophyll being released. Don't do enough prep, and the herbs don't release the essential oils and volatile molecules that are the foundation of their flavor.
Fortunately, bartenders around the world have a solution to this problem, which they use when garnishing drinks with fresh herbs. In order to get the most flavor out of basil, mint, etc., you don't need fancy knife skills or a mortar and pestle. You just need to slap them.
First the technique: place a few leaves or sprigs of your chosen herb in one palm. Then give it a good smack. Boom, you're done. Bon Appetit has a great Vine of it here. Remember, you don't want to put too much in your hand, or the slap loses its efficacy. Just enough for a thin, even layer should do.
Now, what exactly does the slapping do to the herb? In the August/September 2014 issue of Cook's Country, the editors spoke with Tom Schlesinger-Guidell, an expert mixologist. He said, "Depending on the type of herb, it breaks the outer cell structure of the herb, releasing the aroma. And much of what we taste actually comes through a sense of smell."
Cook's Country went on to test the technique, using untouched basil and mint in a salad, and slapping/rubbing the same herbs in a second batch. Tasters said that the slapped herbs had much more flavor and aroma before they were added to the salad, but didn't taste as strong when they were mixed in with the other ingredients.
Our verdict? Use this technique when you're using herbs as a garnish/finishing touch and really want their flavors to stand out. If your herbs are being incorporated into a dish, then you can skip the slap and just chop instead.
Would you slap your herbs?