Graham is known to market-goers in Mornington and Red Hill as well as further afield for what buyers say are "spectacular" cupcakes.

Smallman's studio and gallery is amid her garden and vineyard and she specialises in portraits, landscapes and still lifes. She and husband Rod make Chirping Bird wines on their property.

She said: "I'm really excited to finish my first Archibald entry. Painting Jen over eight weeks was fun; she's larger than life, and her cooking and personality fill a room and that's what I wanted to convey."

Smallman has painted since she was young, inspired by her father, a watercolourist. She studied fine art in Gippsland, but took a break from creating art to raise three boys. She is creating and selecting works for a first public exhibition later this year.

The portrait was unveiled at a private function on Friday night before being packed and sent to Sydney for judging. The winner of the $50,000 prize will be announced on Friday, March 26.

The Archibald Prize for portraiture is named after Jules François Archibald, editor of The Bulletin at the turn of the 20th century who commissioned John Longstaff to paint a portrait of the poet Henry Lawson.

When Archibald died in 1919, he left 10 per cent of his estate of £89,061 for an annual art prize.

In 1921, the first Archibald Prize of £400 was awarded to WB McInnes for his portrait of Harold Desbrowe Annear, the 'rock star' architect of the time who designed or upgraded 10 houses in the region including Cruden Farm in Langwarrin for Sir Keith and Dame Elisabeth Murdoch; Mulberry Hill in Baxter for artist Sir Darryl Lindsay and his wife Joan, author of Picnic at Hanging Rock; Westerfield in Frankston South for Sir Russell Grimwade (with the property to be bisected by the Peninsula Link freeway); and Delgany in Portsea for Harold Armytage and his sisters.