Two months after “I’m Just Ken” debuted on Billboard’s Hot 100 chart, writer and producer Mark Ronson broke down the making of the Ryan Gosling breakout Song at a “The Music Behind Barbie” event in Los Angeles.

Joined by Barbie soundtrack producers Kevin Weaver and Brandon Davis, along with music supervisor George Drakoulias, at the Grammy Museum on Wednesday, Ronson revealed that Greta Gerwig initially came to him with the idea for two main songs.

“She sent me this funny PDF that her and Noah [Baumbach] had scribbled, like Barbie’s song should be about the world is perfect and everything’s great and there are no shadows and everything’s great because everything’s always great and that will be great. Like just all these silly lyrics,” the producer said. “The Ken song was like, ‘I love horses but they also make me mad.’ And it said Barbie and Ken hit songs, which is always like a funny thing to send to a songwriter, ‘Just give us two hit songs.’”

He remembered reading the script and coming up with the lyric “I’m just Ken, anywhere else I’d be a 10,” saying, “I wasn’t thinking about it like, that’s funny; I felt like this poor guy, like that sucks. Never a parody or never like a meme.” Ronson sent a demo of the song to Gerwig, who then played it for Gosling. “Next thing I know, she’s like, ‘Ryan wants to sing the song.’ And I was like, ‘Really?’ She goes, ‘Yeah, he said it speaks very deeply to him.’ And I was like, ‘Is he being ironic?’ And she was like, ‘I don’t think so.’”

Ronson also revealed Gosling’s reaction to its success on the music charts, noting, “He kind of feels like someone who doesn’t get caught up in the hype from the little bit that now I know about him,” noting that he would send Gosling updates on the major milestones “I’m Just Ken” was hitting. “Even he’d be like, ‘This is so surreal, I don’t even know what to tell you.’ I think he’s a real musician, he loves music, and I think he was really touched by that and like when Slash played on it, you know? So there’s certain things that he’s been really, I think, excited about,” he said.

The conversation also touched on the album’s other breakout songs, as Weaver said, “We had so many artists who wanted to be a part of this that we ultimately couldn’t find spots for all of the artists cues for all the artists that wanted to be involved.” Billie Eilish was of course one of those artists who did make it on, with her hit “What Was I Made For?”

Ronson joked that after showing her and Finneas some of the movie, Eilish sent “this very like sweet, harmless text that said like, ‘Wrote a song today’ with like a wink smiley face. We had no idea like a week later we were going to receive the most devastating ballad.” The producer also told the crowd that Gerwig and Margot Robbie both teared up the first time they heard the song.

Another of the album’s biggest songs is “Barbie World” by Ice Spice and Nicki Minaj, which was in danger of not happening had it not been for Gerwig’s direct involvement.

“From the very beginning, we had felt like having Nicki, who is Barbie essentially, be a part of this thing. We kind of continued to hone in on the idea of having her do the flip of ‘Barbie Girl,’ and it’s just interesting because there were many moments when she was doing it and there were a lot of moments when she wasn’t doing it and it kind of was happening and not happening,” Weaver recalled. “We were getting to a point where Nicki actually cut the record and it was incredible. We knew we loved it and Greta loved it, it was cutting the end of the picture [but] we were having a hard time getting it done.”

“We went to Greta and asked Greta if she would write a letter to Nicki, and Greta wrote this beautiful note to Nicki and basically said like, ‘You are Queen Barb and when I set out to make this film, as I was thinking of artists, you were the first artist that really came to me as somebody that I felt was going to be an important collaborator and contributor to this,’” he continued. “I sent that letter to Nicki and the next morning Nicki hit us back and said that she was 100 percent in.”