Few ingredients bring a brighter flavor or aroma to a cocktail than fresh mint. While herbs are simple enough to use when making a single cocktail, maintaining consistency is a challenge if you’re making drinks for a crowd; to make things easier, use mint syrup. Most recipes suggest steeping fresh herbs in hot simple syrup, which is then strained and bottled—but this process prompts oxidation of the plant’s enzymes, transforming the herbs’ bright-green color into an unappetizing brown. The kitchen trick is to briefly blanch the herbs in boiling water, deactivating the plant’s enzymes and preserving the plant's fresh color as it contributes its flavor to your syrup.