The triumph gave trainer Willie Mullins a sixth victory in the last seven runnings of the contest at Leopardstown.
Two subsequent Cheltenham Festival heroines in Let's Dance and Concertista are among the champion trainer's recent winners of the Grade Three contest and Shewearsitwell was actually sent off favourite for last year's renewal, but suffered a nasty fall at the fourth flight.
With her confidence seemingly dented, results since have been mixed - but she got back on the winning trail in a Pertemps qualifier at Punchestown last month and was a 15/8 shot stepping back up in class.
The six-runner contest looked a match on paper and that was the way it transpired, with 8/13 favourite Queens Brook leading Shewearsitwell into the home straight.
But it was soon clear that the Mullins runner had more to give in the hands of Paul Townend and she picked up well passing the dolled off final obstacle to seal a four-and-a-half-length verdict.
Mullins said: "It was very good, she wasn't very brave over her hurdles so I was very happy the last hurdle was taken out twice.
"I thought going down the back she wasn't going to race much but once Paul got after her, she just kicked into gear. She improved and enjoyed herself then.
"Paul said they went a right good gallop and he was at his best just trying to keep her in touch with the race.
"She was losing a half-length here and there at her hurdles which wasn't good for her, but she eventually got it right and when it came to staying she outstayed the rest of them."