Gregory Gourdet/Eva Kosmas FloresOne of Gregory Gourdet’s favorite dishes to make is mashed potatoes. But the former Top Chef contestant and founder of Kann, a Haitian pop-up in Portland, Oregon, didn’t grow up eating the classic side dish.“I grew up in a Haitian household—we didn’t really eat mashed potatoes,” he says. Instead, his Queens, New York, family ate a lot of rice. But once he started cooking professionally that all changed. “I made mashed potatoes in pretty much almost every restaura