In an episode airing this week, the MKR judge will send an all-female team packing. It's the first time in the show's nine seasons that Manu and fellow judge Pete Evans have kicked out a team for their behaviour.
So what made Manu snap?
"There was a time we were sitting around the table that was uncomfortable," Manu, 45, tells TV WEEK.
"We have been doing this [judging MKR] for a long time, and there's always a bit of fighting. But this was just taking it too far. It wasn't healthy, and it wasn't nice."
The decision to send one team home wasn't taken lightly. But Manu says the future of the reality show depended on it.
"We don't want to start something that might continue in the next series," he says.
The chef adds the drama that unfolds goes against everything the show's about.
"I hope it's going to be a benchmark for future seasons and remind people why they should enter the competition: to show us you're the best cook in Australia – and that's it," he says.
Two of the NSW teams – sisters Emma and Jess, and besties Sonya and Hadil – have clashed from the start.
This week, things get very personal, with insults flying about each other's appearances. Manu describes the incident as "a bit ugly".
"Sometimes I feel like we have got kids around the table rather than adults," he says.
But being a dad-of-two, Manu has no problem with disciplining kids who play up. In fact, he has no regrets with sending the women home.
"I felt like I was dealing with my 13-year old son [Jonti]," he says.
"I'm used to telling him off. I was ready to take the responsibility and try to change the mood and the competition to where it was supposed to be at."
Manu says he made a "quick decision" at the dinner party, along with Pete and the show's production team.
"It's like having a rotten apple in a box," he explains.
"All the other apples get rotten as well. We had to make a change."
There was no argument from the team who were sent home.
"They just got up and left," he says.
But the remaining teams were all shocked at what had happened.
"I don't think anyone enjoyed it or was pleased with the situation," Manu admits.
"I think everyone was like, 'Oh, my God – what have we [the judges] done?'"
But once the team was gone, he says the tone changed "100 per cent".
"We continued, and the rest of the competition was fantastic," he smiles.
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