An Australian woman on trial for murder says she threw up the toxic mushroom meal which killed her relatives, after binge eating dessert.

Erin Patterson has pleaded not guilty to four charges – three of murder and one of attempted murder – over the beef Wellington lunch at her regional Victorian house in July 2023.

Prosecutors allege Ms Patterson deliberately served toxic death cap mushrooms, but only to her guests. Her defence team say the contaminated meal was a tragic accident, and argue it had made their client sick too.

Ms Patterson told the court she had only eaten a small part of lunch but later consumed two-thirds of a cake, before becoming “over-full” and vomiting.

Doctors have previously told the trial Ms Patterson did not have the same intense symptoms as the other people who’d eaten at her house.

On her third day of wide-ranging testimony, Ms Patterson also admitted she had lied about a cancer diagnosis – which prosecutors say she used to coax the guests to her house – instead of revealing she was actually planning to undergo weight-loss surgery.

She said she had dumped a food dehydrator and wiped her phone in the days after the incident out of fear of being blamed for her relative’s deaths, telling the court her estranged husband had accused her of poisoning them.

Three people died in hospital in the days after the meal, including Ms Patterson’s former in-laws, Don Patterson, 70, and Gail Patterson, 70, as well as Gail’s sister, Heather Wilkinson, 66.

A single lunch guest survived, 71-year-old local pastor Ian Wilkinson, after weeks of treatment in hospital.

The Victorian Supreme Court trial – which started almost six weeks ago – has heard from more than 50 witnesses, and attracted huge global attention.

In the Morwell courthouse, Ms Patterson gave a detailed account of the fatal lunch, saying she had invited her guests under the premise she wanted to talk about health issues.

The 14-member jury heard that Ms Patterson went through “quite a long process of trying to decide what to cook” for the lunch before choosing to make beef Wellington.

The dish – usually prepared with a long strip of fillet steak, wrapped in pastry and mushrooms – was something Ms Patterson’s mother made when she was a child, to mark special occasions, she said.

After deciding the mushrooms she’d prepared tasted “bland”, she said she’d added some dried ones – bought from an Asian grocer in Melbourne months earlier – from a container in her pantry.

Asked if that container may have had other types of mushrooms in it, Ms Patterson, choking up, said: “Now I think there was a possibility that there were foraged ones in there as well.”

Yesterday, the court heard that Ms Patterson had started hunting for mushrooms in locations close to her Leongatha home in 2020, and her long-standing love for fungi had expanded to include wild varieties as they had “more flavour”.

Ms Patterson told the jury she had served up the food when it was ready, and instructed her guests to grab a plate themselves as she finished preparing gravy.

There were no assigned seats or plates, she said.

Mr Wilkinson previously told the trial the guests had each been given grey plates while Ms Patterson had eaten off an orange one. Ms Patterson on Wednesday said she didn’t have any grey plates.

During the lunch, Ms Patterson recalled that she didn’t eat much of her food – “a quarter, a third, somewhere around there” – because she was busy talking.

She conceded she had told her guests she had cancer, but in court explained she told this lie to make sure she had help with childcare when she underwent gastric bypass surgery.

“I remember thinking I didn’t want to tell anybody what I was going to have done. I was really embarrassed by it,” she said.

After the guests left, she cleaned up the kitchen and ate a slice of orange cake Gail had brought.

“[I ate] another piece of cake, and then another piece,” she said, before finishing the rest of the dessert.

“I felt sick… over-full so I went to the toilets and brought it back up again.”

“After I’d done that, I felt better.”

Yesterday, the court heard that Ms Patterson had secretly struggled with bulimia since her teens and was prone to regularly binge eating and vomiting after meals.

Ms Patterson told the court that she started develop gastro-like symptoms hours after the lunch and took herself to hospital to “get some fluids” two days later. She was “shocked but confused” when medical staff asked if she could have eaten death cap mushrooms.

While in hospital for observation overnight, Ms Patterson said her former husband Simon asked her about a dehydrator she owned.

“Is that how you poisoned my parents?” she told the trial he’d said to her – something Mr Patterson denies.

After this encounter, she’d been “frantic”, Ms Patterson said, and upon being sent home had disposed of her food dehydrator at the local tip.

“I had made the meal and served it and people had got sick.”

“I was scared that they would blame me for it.”

The court also heard that Ms Patterson erased the data on one of her phones several times – including while police were searching her house – because she did not want detectives to see her photos of mushrooms and the dehydrator.

Ms Patterson will continue giving evidence on Thursday, before prosecutors will have the opportunity to cross-examine her.