The Scot romped to victory over two rounds at Kedleston Park Golf Club in Derbyshire finishing five shots clear of runner-up Keely Chiericato, the 2018 winner.
MacRae, who returned an eight under par total of 140, and Chiericato were the only two players in the field to break par in damp and gusty conditions.
The 37-year-old, who represents Gleneagles Hotel, said she put all thoughts of a hat-trick triumph to one side as she concentrated on her final round.
“I just tried to hit good shots and it worked out OK,” she said. “I didn’t know what my score was approaching the final hole. I knew I was playing well and scoring well. But I didn’t want to think how many under par I was because that’s when you start to get nervous.”
Chiericato prevailed in a play-off against MacRae to win the title in 2018 and finished second to the Scot last year, just one shot behind. But this was an emphatic victory for MacRae whose record in this event is all the more remarkable given her battle with cervical cancer in 2019.
Her form has afforded her several opportunities on the Ladies European Tour recently, and she also now has an eye on qualifying for the AIG Women’s Open at Carnoustie next month.
“I’ve been pretty lucky this year because the ranking has gone quite far down for LET events so I’ve had a few starts and I go away next week to Finland,” she explained.
She will look to take that form to final qualifying for the Women’s Open at Carnoustie, a reward for finishing in the top three of the OCEANTEE-supported WPGA Championship.
“That’s a big plus,” she said. “It’s great The PGA has given us that opportunity to three of the ladies to get to final qualifying. And being at Carnoustie and pretty close to home, I’d love to play in the main event.”
She will be joined at the qualifier by Chiericato and Jessica Smart who finished tied-third with Katie Rule on three over par but claimed the last spot on countback.