Camila Cabello and Shawn Mendes have come a long way after turning their close friendship into romance this year, and now we’re learning exactly how the magic unfolded. The singer, whose second studio album Romance comes out in December, sat down with Rolling Stone for an in-depth interview about her upcoming release as well as her budding relationship with the hunk and revealed the moment she knew he was going to become more than just a friend. “During ‘I Know What You Did Last Summer,’ I really bonded with him as more than a friend,” Camila admitted about the 2015 collaboration with Shawn. “I think he did, too, but we were both really young, and he was experiencing the pressures of his career. I don’t think we knew what to do with those feelings. It was this awkward thing where we both liked each other, but we weren’t together.” Since the fireworks went off both literally and figuratively, the lovebirds have been seen expressing major PDA on numerous occasions and are the epitome of a young duo in love.