Shiffrin has quite a story to tell David Letterman as a guest on his show next Tuesday.
With the victory, the Vail, Colo., native went a long way to fulfilling predictions she can follow teammate Lindsey Vonn as a superstar in Alpine racing, and be one of the big profiles at next year's Sochi Olympics.
The manner of victory was truly impressive.
"I was really overcome with emotions after the first run, being so far out," said Shiffrin, who regrouped with her coaches and parents, Jeff and Eileen, in the 2 1/2-hour wait to rectify the damage done by an uneasy opening run which placed her fourth as Maze led.
"Everyone just said, 'What are you holding back for? Go out and have some fun and try to dance with the gates and see how fast you can go,'" Shiffrin recalled.
Needing to finish ahead of the Slovenian, Shiffrin had a tentative start to the second run but blazed down the bottom part of course for the fastest time of the afternoon.
When first-run leader Maze crossed the line in third, Shiffrin put her hands to her face and sank to her knees in the finish area.
"I didn't know I could make up all that time in one run," she said. "It's amazing. I am still trying to find my best skiing but this was my best run of the season."
It was so good that only one skier, Bernadette Schild of Austria, was within a second of her time in the afternoon. Shiffrin finished in a combined time of 1 minute, 55.60 seconds, with Schild 0.20 behind in second. Maze trailed by 0.35.
Maze had already clinched the overall World Cup title along with the giant slalom and super-G disciplines but was still visibly distraught at letting slip such a big lead. While the American paraded her crystal globe in front of photographers, Maze stood with her head buried in her arm, sobbing.
"I didn't lose the slalom season just in this race," Maze told reporters from her native Slovenia. "I made a lot of mistakes and I had a chance to win it before Lenzerheide."
The 29-year-old Maze praised Shiffrin as a "really big talent, one of the biggest. She did a great job."
Shiffrin was quick to pay tribute to her rival, who took two World Cup records from Austrian great Hermann Maier: overall points scored and podium finishes in 23 races.
"I actually want to thank Tina Maze," Shiffrin said. "She's probably going to punch me after this, but she's been very inspiring and helped me get to where I am. She's really my greatest idol this season."
Shiffrin's mother was also nervous as she watched on, clapping enthusiastically as she leaned over a railing in a quiet VIP zone at the edge of the finish area.
"Un-be-lievable," Eileen Shiffrin told The Associated Press seconds after her daughter was declared champion. "She dug so deep in that second run. Oh my God, she finally skied the way she can ski."
That form has won admirers across the sport
"That girl takes pressure and skis like the wind," U.S. teammate Julia Mancuso wrote on Twitter.
International Ski Federation president Gian Franco Kasper compared her poise and calm to perhaps the greatest World Cup skier.
"Perhaps (Ingemar) Stenmark at that age was already one who was so cool, he did not realize it," the veteran official told The Associated Press. "But for a girl of that age... not that I remember."
Shiffrin seems to be accelerating past Vonn, who her family believes was once Mikaela's babysitter back in Vail.
Vonn was 20 when she won her first World Cup race, 23 when she secured her first season-long World Cup title in any discipline, and 24 before winning her first major gold medal, at the 2009 world championships.
Shiffrin already has that trio of accolades three days after her 18th birthday.
She is the youngest World Cup slalom title winner since Christa Zechmeister of West Germany 39 years ago, and the first American World Cup slalom champion since Tamara McKinney in 1984
After a breakthrough season, which finishes with a giant slalom on Sunday, Shiffrin will return to face the media spotlight back home in the U.S. today after four months racing in Europe.
First up is an appearance on "Late Show with David Letterman" in New York City.
"Yeah, Letterman, I am so excited about that," said Shiffrin, who will graduate from Burke Mountain Academy in the summer. "I hope I don't trip when I'm going up on stage.
"I spill things, I break things and I drop a lot of things. You would not think I would be good at slalom."
WOMEN'S GS: Also in Lenzerheider, Switzerland, Tina Maze got the anger out of her system Sunday, one day after her heartbreaking World Cup slalom title defeat to American teenager Mikaela Shiffrin.
Maze won the season-ending giant slalom race to complete the most statistically dominating year since the World Cup started in 1967.
Still, losing the World Cup slalom title to Shiffrin's thrilling second-run performance Saturday still burned for a skier who described herself as "addicted" to her sport.
"That's why I could put out some anger today," Maze, smiling again 24 hours after sobbing in the finish area, told reporters. "Yesterday, I had some disappointments. If I didn't do good today, I would not be 100 percent happy."
Maze performed her trademark celebration cartwheel in the finish area after first-run leader Tessa Worley of France fell 0.35 seconds behind her winning two-run time of 2 minutes, 16.67 seconds. Lara Gut of Switzerland was third, 1.38 back.
The Slovenian racer's 11th World Cup victory this season extended her record overall points total to 2,414. Austrian great Hermann Maier set a mark of 2,000 in the 1999-2000 season.
MEN'S GS: Also in Lenzerheider, Switzerland, Ted Ligety capped his dominant season in giant slalom with a sixth World Cup win Saturday, fueling comparisons with the best GS skier in history.
The American skier joined Ingemar Stenmark as the only men in the 47-year World Cup history to get six GS victories in a season. Stenmark's 10-race sweep in 1978-79 is the record.
"It's very surreal for any ski racer," Ligety said of being likened to the Swede. "He is at another level that's not really achievable."
Ligety's 17 career World Cup wins in his specialist event are a long way from Stenmark's 46, though the latest came with similar authority.
He raced smoothly down the steep slope in a two-run time of 2 minutes, 14.76 seconds, beating overall World Cup winner Marcel Hirscher by 0.37 seconds.