"I usually just sing in the shower, but @thedancingfox convinced me to record a duet with him," Miranda revealed on Twitter on Sunday. "Not a career change, just a bit of fun!"
Australian theatre star Bobby later posted a message on his Instagram page. "I convinced Miranda Kerr to record a little song with me for my album… It's out late March. You're The Boss."
A source close to mum-of-one Miranda, 30, confirmed that "she has no plans to embark on a singing career", but added, "she loves music and just thought this would be fun".
According to the Mail, Bobby jetted into New Zealand, where Miranda was working on a photoshoot, and they recorded the song in just one night.
"Miranda was amazing to work with," a spokesperson for Bobby said. "She didn't take herself too seriously – she just got into character and had a ball recording it."
This is not the first time that Miranda has sung in public. In 2012, she featured in a Japanese advert for Lipton Ice Tea, pretending to be a waitress singing to customers in a bar.