Aida Batlle grows coffee on her family’s farm in the hills surrounding El Salvador’s Santa Ana Volcano. Like generations before her, she had little use for the skin that encases the beans, so she’d turn it into cheap fertilizer or, more frequently, trash it. Then one day, walking past some husks drying in the sun, a smell hit her, a good smell: hibiscus and other floral aromas. It dawned on her, she says, that some value might be extracted from what she had long considered refuse. So she steeped the husks in hot water and had a taste. “Immediately I started calling customers to try it,” she says.