The pair have presented and judged the BBC cooking show together since 2005 and long batted off rumours that they do not get on when the cameras stop rolling.
Torode, 55, has now reiterated to the Radio Times: "It's well documented that we don't socialise outside of work. We've never been to each other's houses. We've never really cooked for each other.
"We spend a lot of time together, sharing a lot of things: emotion, food, pressure and changing people's lives. And 17 years on, it's still a relationship that is calm and in good stead. I think it's an amazing thing."
Wallace added: "We trust each other completely. We feel safe with each other. We know that the other one isn't going to – on camera, anyway – ridicule the other one.
"We don't fight for space. We don't fight for time. There is no ego clash.
"People are really interested in my relationship with John. I think because we're so friendly on screen, they find it really difficult to understand why we're not as friendly off screen."
But the pair revealed that despite keeping their relationship strictly professional for so long - they do always share one meal together when filming away from home.
Wallace said: "We do have something that's become a bit of a ritual, and that's on location, when we go away on foreign travel. John and I go off and we have lunch together on one day.
"It's just me and him. We buy a nice bottle of wine and we can chat about anything."
Wallace married fourth wife Anne-Marie Sterpini, 34, in 2016 and they have a 22-month-old son, Sid.
Torode married former Holby City star and Celebrity MasterChef 2010 winner Lisa Faulkner in 2019.
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