Shiffrin slaloms to all-time record 87th victory in Sweden
Shiffrin, who took her first career victory in December 2012 in the same resort, equalled the all-time record of retired Swedish great Ingemar Stenmark in a giant slalom on Friday.
She became the most successful female World Cup skier of all time in January when she passed compatriot Lindsey Vonn's tally of 82 wins.
"Pretty hard to comprehend that thought," she said when asked by a television interviewer how it felt to be the greatest of all time.
Stenmark's record had stood since 1989, and the Swede saluted her achievement.
"She deserves the record more than anyone else," he told the FIS website, standing by an earlier prediction that Shiffrin would soar past 100 wins.
"She is a complete skier. She has a good technique, but it’s not only that. She has physical strength, she has a strong head - those things combined make her so good.
"And she’s smart too. She doesn’t have to race at 100% speed. She knows that the others have to go beyond their ability (to beat her) and that they will make some mistakes."
Shiffrin was in a class of her own on Saturday, leading by 0.69 seconds after a first run she described as "pretty perfect".
Swiss skier Wendy Holdener (29) finished 0.92 seconds behind the American having posted the best time in the second run with Anna Swenn-Larsson (31) rounding out the podium.
"You have to be smart but also I just wanted to be fast too and ski the second run like its own race,
"I did exactly how I wanted and that's amazing.
"I need to do a really good second run as well but I felt pretty perfect on the first run so I'm very happy with that," said Shiffrin earlier in the day, who has already won the slalom World Cup crystal globe as well as the giant slalom and overall titles.
"Yesterday was such a big day it's hard to imagine another day happening like that," she told Eurosport television.
"So many things can happen, especially in slalom when you're pushing the limit. You can be off the course in one hundredth of a second, so I'm not taking that for granted. It might not happen but maybe it can happen."
Shiffrin had said after the first run it was hard to imagine another day like Friday but there was a surprise in store after she crossed the line.
"It got a little bit more emotional when I saw my brother and sister-in-law in the finish as I didn't know they were coming," she said.
"Taylor, Kristi and my mum (Eileen) were the first people that I saw and I was, like, 'What are you doing here?. We're in Sweden, we're not in the US, we're not even close'.
"That just brought everything...just total mess then. What an unbelievable day."
Shiffrin had already won the slalom World Cup crystal globe, along with a fifth overall title and the giant slalom globe, and Saturday was her 13th win of the season.
The 2014 Olympic slalom champion also won gold in the giant slalom at last month's world championships in France and silver medals in slalom and super-G.
Shiffrin, who turns 28 on Monday, still has more races to come before the season is done with the World Cup finals in Soldeu, Andorra, next week.
Whereas Stenmark's success in the 1970s and 80s was limited to slalom and giant slalom, Shiffrin has also won in downhill, super-G, combined and parallel as well as the two technical disciplines.
"To reach the top and be able to keep winning so many competitions, you have to try to find a new motivation, new goals," said Stenmark. "And that’s what’s hard when you’ve been around for a while and when you’ve won a lot.
"She is starting to get, and is already, good at super-G. And she can do downhill races well too, so perhaps that’s a new motivation for her."
It was a poetic weekend for Shiffrin, who took the first World Cup victory of her career in Are in 2012.