Tuned up with a recent Cranbourne barrier trial win in which she beat stablemates and fellow star fillies Tulip and Catchy, Formality was presented in top order by the Hayes Dabernig training partnership.
Formality(images Steve Hart) jumped straight to the lead for Kerrin McEvoy and led throughout defying a determined challenge from runner-up Alizee to win by a long head in 1:08.83.
"I love the way she fought back, she was so tough down the straight," said Ben Hayes.
"The main plan for her is the Golden Rose. She'll run in another three year-old race in two weeks time and then into that race."
Formality was a modest $120,000 Inglis Easter purchase from the Coolmore draft by Inglis as agent and runs for Coolmore and partners for whom she has won three of six starts earning $469,400.
"She's always been a big strong filly, but she's really matured now," Hayes added.
"She is a big eater at home and that's a great positive."
Bred by Dr K Tan and foaled and raised at Coolmore, Formality is the best of four winners from four foals to race from 2009 Singapore Horse of the Year, Jolie's Shinju (Jpn), a daughter of the Halo sire Jolie's Halo.
Jolie's Shinju is due to foal to Choisir.
Formality is the first stakes-winner of the new season for Coolmore's champion sire Fastnet Rock.