Sheena Zadeh-Daly’s buzzy clean makeup brand, Kosas Cosmetics, has gone viral time and again, and if you’re one of the millions of people who have purchased the brand’s best seller—the Revealer Concealer—or any of its other innovative products, you know why. Today, Kosas products are sold in retailers such as Sephora nationwide and are beloved for their comfortable, weightless feel. Not to mention, they’re clinically proven to make your skin better. But before Zadeh-Daly was creating one of the fastest-growing prestige makeup brands in the U.S., her career looked quite different. After studying biological sciences and working as a microbiologist in a lab—experiences that have certainly helped in the development of Kosas—Zadeh-Daly went on to work in the art world. It was actually there, in a portrait painting class, where she began to think about color not just as paint but also as potential lipstick shades for a makeup brand she’d been secretly dreaming up for years.