Lee had her four-shot overnight lead slashed in half early in the final round before hanging on, then surging gamely for a three-shot triumph in more extremely trying conditions at PGA Frisco's windswept Fields Ranch East course.
The 29-year-old bogeyed three of the first six holes in an understandably anxious start before steadying to close with a sufficiently sound two-over-par 74 on championship Sunday (Monday AEST).
"Just stick to my game plan. It's a battle against myself pretty much, especially with how tough the conditions were this whole week," Lee said of her final-round approach.
"Not just today. It's just amplified today because it's a major Sunday, but yeah, just be patient, take every shot as it comes.
"I pretty much I saw every single leaderboard and I knew exactly where I was, pretty much all of today, so I checked the scores and then I just came back to each shot and tried to execute it the best that I could, so I played within myself today."
Lee finished with a 72-hole four-under 284 total to deny fast-finishing American Auston Kim (68) and Thai Chanetee Wannasaen (68) improbable comeback victories at the third women's major of the year.
In adding to her 2021 Evian Championship triumph and 2022 US Open success, Lee completed the third leg of women's golf's fabled grand slam to edge ever closer to a place in the sport's Hall of Fame.
The British Open and Chevron Championship are the only two majors to elude Lee.
Just as significantly, Lee joined legends - and fellow females - Karrie Webb and Jan Stephenson as only the third Australian golfer in history to win three different major championships.
With three majors, Lee also surpassed the great Greg Norman and David Graham on Australia's all-time majors winning list.
Lee now only trails seven-times major champion Webb and five-times British Open winner Thomson.
Sunday's victory also snapped a 19-month winless run, the longest drought of her decorated career, and secured Australian women's sport's highest earner another monster cheque of $US1.8 million ($A2.8 million).
Perhaps most gratifying of all, the Perth prodigy also buried the demons from last year's spectacular final-round crash at the US Open.
Lee opened up a three-stroke back-nine lead only to collapse down the stretch to finish tied for ninth at Lancaster Country Club.
The sister of PGA Tour star Min Woo Lee paid a heartfelt tribute to her family after pocketing the monster winning and enhancing her status as Australian sport's highest-earning women's athlete.
"At this point in your career, I mean, my parents have sacrificed so much for me to be here," Lee said with her mother and career-long coach greenside.
"I can't say more things than I've already. It's just extra special that I could win in front of them and obviously wherever Min is, he's supporting me out there.
"He's a social media nut so he's all on top of that, so it is really cool.
"And obviously my dad's back in Oz - I don't know what time it is there - but he's tuning in and they've always got my back, so it's really nice and it's great support and unconditional."
