Melissa Leong teases MasterChef contestants in tonight’s episode

Melissa Leong caused giggles across the kitchen with a cheeky warning to the scrambling contestants during tonight’s challenge.

In a mistake many schoolchildren have made in the past, Melissa Leong has joked with the MasterChef stars about being called “mum” under the pressure of the kitchen.

In a snippet from tonight’s episode provided to news.com.au, while announcing how much time is left, the contestants reply with the familiar chant of “Yes Chef”.

But one contestant was left looking rather awkward as Melissa responded with a laugh: “I’m not a chef. Just don’t say ‘yes mum’ which I’ve heard before”.

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Food writer Mel was quick to warn the contestants not to call her ‘mum’ in the kitchen. Picture: Channel 10.

She’s not the only judge to cop it.

Jock Zonfrillo, 43, looked mortified last season of MasterChef when Katy Perry called him “daddy” during a guest appearance.

The US singer surprised contestants with her appearance during an immunity challenge, asking Jock to cut her meat for her as she said, “Put it in my mouth daddy!”

The moment was no less than iconic. Picture: Channel 10.

Opening up about the risque joke to Studio 10, Jock said: “Look, it’s embarrassing.”

He added trying to keep Perry under control during filming was an “absolute nightmare”.

“Katy Perry is a dynamo. She came in the kitchen, she broke all the rules,” he said

“And the twist was actually on the judges, because trying to control her and contain her was an absolute nightmare.

“She was hilarious, absolutely hilarious, but she didn’t stick by any of the rules, which we loved of course. It made for a hilarious episode,” he added.

Tonight, the new crop of contestants will compete in a mystery box challenge to earn a spot in tomorrow’s immunity cook.

MasterChef Australia continues tonight from 7.30 on Channel 10.