Erin Patterson has conceded she added foraged wild mushrooms and made “deviations” to a beef Wellington that would allegedly kill three of her former in-laws.

The 50-year-old was giving evidence for a third day in her Supreme Court trial in regional Victoria.

Lines of people curious to catch a glimpse of Patterson during her time in the witness stand have stretched from the Morwell court’s doors each day this week as her trial continues into its sixth week.

She has pleaded not guilty to three murders and one attempted murder over the July 2023 lunch she served to Don and Gail Patterson, 70, and Gail’s sister Heather Wilkinson, 66.

All three died in hospital days after eating the meals.

Heather’s husband Ian Wilkinson was the sole surviving lunch guest.

On Wednesday, Patterson, who maintains the poisonings were not deliberate, outlined how she made the deadly beef Wellington.

Most of the ingredients – mushrooms, eye fillet steaks, filo and puff pastry, potato mash and green beans – were bought from Woolworths, she told the jury.

Patterson made “deviations” to the RecipeTinEats recipe, including buying 10 beef tenderloin steaks after being unable to find a log of beef. She also used filo pastry instead of making a crepe, and left out mustard and prosciutto because Ian didn’t eat pork.

She recalled starting early on the day of the lunch by frying garlic and chopped shallots before adding two tubs of mushrooms she bought from Woolworths to make the duxelles, or the mushroom wrapping.

“I cooked it down. I tasted it a few times. It seemed bland so I decided to add the mushrooms from the grocer I had in my pantry,” she told a full courtroom and 14 jurors.

Defence barrister Colin Mandy SC asked her to reflect on what may have been in the pantry container of mushrooms, which she said she bought from Melbourne.

“Now I think that there was a possibility there were foraged ones in there as well,” Patterson said.

She previously said she began foraging for wild mushrooms during the Covid-19 pandemic in 2020 at Korumburra Botanic Park, on her 1.2-hectare properties in Korumburra and Leongatha, and along a rail trail leading out of Leongatha.

Mandy asked Patterson “do you accept there must have been death cap mushrooms” in the lunch she served to her former husband’s family. She answered: “Yes.”

Patterson recalled making six beef Wellington parcels, ensuring they would be done and resting out of the oven by 12.30pm, when her guests arrived.

After she plated up five of the dishes with mashed potatoes and green beans, the group sat at the table.

Patterson recalled Ian, Don and Heather finishing their entire plates, Gail eating “quite a lot of hers, not all”. It was finished by Don, while Patterson ate about a quarter to a third of her own plate.

“I was talking a lot. I was eating slowly,” she said.

Her in-laws left because Ian had a meeting at his church.

Patterson cleaned up the kitchen and put things away, admitting she also ate the rest of the cake Gail had brought.

“I felt sick. I felt over-full. So I went to the toilet and brought it back up again,” she said.

Patterson recounted feeling a bit better, with only symptoms of loose stools that afternoon and night.

-AAP