Archaeologists working on the Bendigo bakehouse ruins were excited to unearth the 3.9m-long and 3m-wide stone oven built on the back of the bakery and described the find as "regionally significant".
Mrs Valk (85) never met her great-grandfather, James Lawrence, but spent some time with his youngest son, Arthur.
James, or Jimmy as he was known, established bakeries in goldfields diggings including Nokomai, Nevis, Cromwell, Arrowtown and Cardrona as well as at Bendigo.
"Although he had other jobs too, and eventually owned three gold mines, he was baking bread right up until he died, aged 59, on April the 1st, 1900," Mrs Valk said.
He is buried in the Cromwell cemetery.
Mr Lawrence lived in Bannockburn and also ran a bakery from his home.
Mrs Valk said her great-uncle Arthur shared a few yarns about his father.
"The bread dough would be all mixed up and left to rise in the tins and their father would then knock it down and make the loaves, then bake it.
"Often, though, when the kids came home from school, the old man would be asleep on the bags of flour, the dough would be spilling out of the tins, and the fire would be out.
"He'd most likely had a drop or two of whisky."
When she was staying with Arthur in Sydney, he made her bread "so I could say I'd had bread baked by a Lawrence".
"It runs in the family. They can all bake."
Mrs Valk's grandfather was Jimmy's son, Thomas, and her father was his son, Ted.
Ted built a home for the family in 1923 in Bannockburn, a two-room place that cost him 90, including the coal range and water tank.
He started a business as a local carrier and delivered mail, papers and groceries throughout the district, including a mail and grocery run to the Nevis.
Mrs Valk worked as a home help and child minder during her teenage years and also had a stint at a bakery called the Golden Crust in Cromwell.
"I used to help Dad with the bread deliveries too, during the war years when there was a shortage of bread bags to wrap the bread in. Sometimes we'd just have to leave the unwrapped fresh bread on the gatepost on the roadside and just hope the cows didn't come and clean it up after we'd gone."
