It used to be that only a handful of wineries made sparkling wine in the U.S.—namely a handful in California owned by Champagne houses such as Chandon and Roederer. The traditional Champagne process takes a lot of time, equipment, and manpower, meaning the bar to entry was always high. But winemakers in the past few years have embraced a style of sparkling wine called pétillant naturel (pet-nat), in which wines finish in the bottle, without the usual addition of yeast and sugar for a second fermentation. A much quicker and cost-efficient process, it’s allowed smaller producers to gain a toehold in the sparkling wine market, too. But this sparkling trend expands beyond California’s borders, with producers from Oregon to Vermont working in whatever way they can to appease the growing American interest in sparkling wine.