Vonn captured the event, her 47th World Cup victory, with a time of 1 minute, 26.16 seconds, 0.61 second ahead of Hoefl-Riesch.
Tina Maze of Slovenia placed third and American Julia Mancuso came in fifth with a 1:27.14.
The win gave the United States the Cortina Trophy, which honors the most successful team at the annual World Cup events at Cortina d'Ampezzo.
"We definitely wanted to make a statement today and the whole team stepped it up," said Alex Hoedlmoser, coach of the U.S. women's squad.
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