Charlotte Bankes and Huw Nightingale won snowboard cross mixed team gold to secure Team GB's first ever Winter Olympic title on snow.
After heartbreak in their individual events, the British pair made amends with an astonishing performance to add Olympic gold to the World Championship title they won in 2023.
It is the first time Great Britain have won two gold medals at a single Winter Olympics.
GB's only previous Olympic medals on snow were bronzes - for snowboarder Jenny Jones in 2014, and freestyle skier Izzy Atkin and snowboarder Billy Morgan four years later.
Asked how she was feeling, Bankes told BBC Sport she was "lost for words".
"Huw put me in an amazing position, he's been riding extremely well and rode today to his full potential," she said.
"I was in that start gate, knowing I was going for gold."
In an event that sees the men race first, Nightingale crossed the line in second place behind France's Loan Bozzolo to set up Bankes perfectly - and she used her remarkable speed on the board to take the lead and pip Italy's Michela Moioli to the line by 0.43 seconds.
It marked a second successive silver in this event for Moioli and Lorenzo Sommariva, while Bozzolo and Lea Casta took bronze.
Bankes, a former individual world champion and two-time overall World Cup winner, was left crestfallen on Friday when she exited the women's event in the quarter-finals, just as she did four years ago in Beijing, despite being widely tipped for a medal.
Similarly, Nightingale was left wanting much more from himself after exiting the men's competition in the round of 16, but found another level to produce arguably his best and most attacking racing alongside Bankes.
"It's immense. I think we push each other well and for me, I know that Charlotte Bankes is behind me and she's such an incredible rider that it kind of loosens me up," Nightingale said.
"I know that when I'm loose, I can ride really well and I think we've shown that today. The singles were tough but now there are tears of joy."
They had been seeded in 13th place for this event, despite winning the only mixed team World Cup of the season before the Games.
A large British contingent descended on Livigno Snow Park on Sunday to watch Bankes, 30, and 24-year-old Nightingale, with huge union jacks plastered with their images pinned to the front of the fan zone.
The red, white and blue-clad supporters' excitement was palpable as Bankes and Nightingale first won their opening quarter-final, and then their semi-final - despite a broken binding for Bankes in the start gate - to ensure a shot at a medal.
And with only four teams in the final, their chances of a podium finish were high - though in the chaotic world of snowboard cross, where riders can hit speeds of 60mph and the slightest clip of a board can end all hope, nothing is guaranteed.
Bankes looked stunned as she crossed the finish line, coming to a stop at the barriers as the ecstatic Nightingale - who had faced an agonising wait at the bottom of the course - enveloped her in a hug, before sprinting over to the Team GB coaches who were waiting in the wings to congratulate their champions.
This marks Britain's second medal - and gold - of the Milan-Cortina Olympics after Matt Weston's victory in the men's skeleton.

For Bankes, competing at her fourth Winter Olympics, she finally has her hands on the medal that had evaded her for so long.
Widely seen as one of the best in the business, she has 26 World Cup gold medals to her name, and in 2021 became the first British snowboarder to win a World Championship title.
But until this day, the Olympics has never gone her way.
Born in Hemel Hempstead, she moved with her family to France as a four-year-old and represented the country at the 2014 and 2018 Winter Olympics, before changing allegiance to GB after the Pyeongchang Games.
Bankes then went into the Beijing Olympics four years later as perhaps Britain's best chance of a gold, but a crash in the quarter-finals put paid to her hopes and left her devastated.
Her lead-up to these Games was far from ideal either.
In April last year she broke her collarbone, an injury she needed further surgery on in the summer - including a bone graft from her hip - after it was found not to be healing correctly.
She arrived here back to full fitness, yet was left feeling "lost" and incredibly emotional as she failed to find her best form in the women's individual event - before putting that disappointment behind her to secure the medal she had craved.
"For me, it's a relief, to get that medal and show our strength," Bankes said. "That's what's been frustrating me, not being able to show what we're capable of.
"We both didn't perform perfectly in the individual. For me, it was a really bad performance, and to use that to come back and give it everything we've got... it takes that weight off my shoulders, hopefully it takes a bit of pressure off everyone else in Team GB.
"We've got a super strong team and hopefully the end of these Games are going to be even more incredible for the whole of Team GB."
Winter Olympics 2026
6-22 February
Milan-Cortina
Watch two live streams and highlights on BBC iPlayer (UK only), updates on BBC Radio 5 Live and live text commentary and video highlights on the BBC Sport website and app.