Zesting is the process of removing the outermost layer of the peel from citrus fruits like lemons, limes, and oranges. This thin layer, known as the zest, contains essential oils that provide a strong, aromatic flavor. Zesting is commonly done using a zester or a microplane, which allows for fine shavings of the peel without including the bitter white pith underneath. The zest can be used in various culinary applications, such as enhancing the flavor of baked goods, dressings, and marinades. It adds a bright, fresh taste to dishes and can also be used as a garnish for cocktails and desserts, making it a versatile ingredient in cooking.