Condiments have been at the heart of food preservation for most of human history. In fact, the word itself originally referred to any substance that prevented food from spoiling. But condiments have outgrown these utilitarian beginnings, and now hold the power to transform the humblest of dishes into something revelatory. Imagine adding a fiery and aromatic zhug to cool yogurt to make the ultimate saucy accompaniment to grilled meats, or a vibrant...