Tonic water derives its bitterness from quinine, a purified substance derived from the bark of the cinchona tree. Paired with gin, tonic water makes for one of summer's most refreshing cocktails. At Bar Code in Bellevue, Washington, the gin and tonic is made in a unique manner: The gin itself is infused with cinchona bark, citrus, and other aromatics. Then, rather than tonic, soda water is added to make the drink. This recipe first appeared in our June/July 2014 issue with Camper English's story "Miracle Cure."