Schild sizzled on her second run of the day to win the event and tie the record for most wins in the ladies' slalom compiled by Vreni Schneider of Switzerland in the 1980s and 1990s.
Schild started the second run in third place and tore down the slope in 53.26 seconds to win the event with a combined time of 1 minute, 45.17 seconds, 0.33 seconds ahead of second-place Frida Hansdotter of Sweden.
Schild's kid sister Bernadette Schild, led after the first run and wound up in third place with a 1:46.39.
Mikaela Shiffrin of the United States finished 2:11 off the pace in 12th place and Germany's Maria Hoefl-Riesch, who is second in the overall women's standings, got hung up on a gate in the first run and did not finish.
"It wasn't my best day," Shiffrin said. "I was just a bit nervous. Sometimes I don't get that great feeling I want in the morning."
France's Tessa Worley, who won the giant slalom during the weekend, took a serious spill on the first run and was taken to a hospital for treatment of an injured right knee.