The AIS 24-year-old took things easy in the qualifying round, finishing in sixth place, but then stepped it up in the final to make his fourth podium in a row.
French skier Guilbaut Colas collected the victory, his first for the season, with 26.80 points, 0.59 points ahead of the Australian.
Defending World Cup champion Alexandre Bilodeau of Canada rounded out the minor medals on 25.95 points.
"Dale was quite conservative in qualifying," said Olympic Winter Institute CEO Geoff Lipshut.
"Then he put down a very good run in the final after swapping lanes just before it."
"He was very fast, very clean, and it was a great effort to get second. It just shows his great adaptability."
The result stretched Begg-Smith’s lead on the World Cup standings, his 475 points putting him 123 clear of nearest rival, Jesper Bjoernlund of Sweden.
Colas, who looms as a serious medal threat in Vancouver after claiming silver in the opening Deer Valley event, is in third place, despite missing the season’s opening two World Cups.
Ski & Snowboard Australia athlete Matt Graham was in 27th position, an impressive performance in just his second World Cup appearance, while Begg-Smith’s AIS team-mate Sam Hall finished in 35th place.
Disappointment for Cooper
However there was disappointment for Australia‘s No.2 moguls skier Ramone Cooper, who was ruled out of the event with a major knee injury sustained in training the previous day that will also see him miss the Winter Olympics.
The Perisher Blue 21-year-old had started the season with a ninth placing, the second top 10 of his career, and was looking forward to a strong performance at the Games.
"I was holding onto a glimmer of hope that it was not as bad as first thought," Cooper said.
"But the MRI results show a torn PCL (posterior cruciate ligament), partial MCL (medial collateral ligament) tear, a partial lateral meniscus tear, another tear on something I’m not sure of, and bone bruising."
"I’m extremely devastated."
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