The feud, which has been kept secret for years, was brought to light during Amber and Mel's Instant Restaurant, which they called Salty Secrets.
"Do you want to hear about salty secrets from us?" Manu asked the group, to which they all excitedly responded, "Yes!"
"The salty secret is Colin and I started on the wrong foot," he began. "Because when I started TV, most chefs in the industry thought I’d sold my soul.”
"I said he'd sold out," Colin told the contestants.
"They said I was no longer a chef, I was a TV celebrity," Manu explained, adding that he was left shocked when he was told Colin would be his co-host on the show.
"I got told, 'Oh we’re going to bring in a new chef - Colin Fassnidge.' And I went, 'What?! The guy hates my guts and I hate his guts'," Manu said.
Colin looked sheepish, adding, "So day one of MKR, I turn up and they’re like 'Have you met Manu?' And I was like, 'S***'.
"We did the season. It was a tough learning curve for me."
However, once they finished shooting the season, the pair set aside their differences, with Manu explaining, "So we finished the show, I went into my room, he went into his. And suddenly I heard [knocks on table], open my room and he went 'I would like to apologise for being an a***hole.'
"And we've been good friends ever since!"
Fans loved the story, with one Instagram user writing, "It's a chef bromance now."
"Awwww love these two," another said.
"Manu and Colin have such great banter and you can see they truly love each other," one Facebook user added. "Beautiful Bromance."
"Oh those two are the cutest, such a quality friendship," another agreed.
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