When Rose Matafeo won the Edinburgh Comedy Award for Best Show at the Edinburgh Festival in August the acclaim was widespread. The director of the awards, Nica Burns, described the London-based New Zealander as the “voice of millennials”.

That’s not how the chatty 26-year-old sees herself. Sitting in her Soho Theatre dressing room during the sold-out transfer of Horndog, she laughs at that quote: “I am a millennial and I talk about my life, so technically it’s true, but I don’t think I speak for a generation. I felt like I had massive imposter syndrome as soon as it happened.”

Despite having been a stand-up since her teens, she had a crisis of confidence during the Edinburgh Fringe. “Halfway through I was texting my friends, saying: ‘Do you ever feel that you are not really a comedian?’.”

She might seem confident onstage but offstage she exhibits a self-deprecating streak when talking about winning a prize won by stars like Steve Coogan and Lee Evans: “I’ve never experienced such weird shock. I’m an ambitious person secretly but winning was an out-of-body experience.”Anyone who has seen Horndog, however, will know that the prize and the accompanying £10,000 is deserved. Her set is a high-energy love letter to her intense youth, when she was obsessed with films, Franz Ferdinand and, eventually, boys. “Go hard or go home” was her motto. She probably wasn’t the only teen hooked on Bridget Jones — but how many watched it on DVD every night?

Recent accolades have reassured her that she is no imposter. Last week Franz Ferdinand’s Alex Kapranos actually turned up to see her show. She even received a congratulatory tweet from New Zealand PM Jacinda Ardern, to which Matafeo responded with: “Holy crap, that’s my prime minister hahahahaha.”

The “voice of millennials” tag comes from the fact that her material is so relatable. “I wanted to write a show about the excitement of being really into something when you’re young,” she says. Matafeo talks about being part of the “in-between generation” growing up at the dawn of the internet. The world was a click away. As long as your parents didn’t need to use the landline.

Horndog starts with Matafeo playing ping pong with fans onstage, and after folding the tennis table away the pace rarely lets up. She is a tornado of fun. The only point where she is more considered is when she talks about a disturbing experience a few years ago when a male comedian made a sexist remark about her body at a gig.

At the time she dismissed it but when the stand-up in question messaged her recently to apologise it made her think about the incident again. Her response, however, was nuanced. It may have been an inappropriate workplace comment but, as she acknowledges onstage, he was also saying she looked good. It’s a take on #MeToo that might not endear her to everyone but Matafeo is just being typically frank.

“I don’t think what I’m saying is necessarily correct, I’m just being honest about how complex those situations can be. Reactions can be mixed up and not always right.”

Matafeo is, however, keen to highlight that everyday sexism remains a problem. “You get used to such micro-aggressions, those sneaky remarks. Especially in comedy: when the mood is meant to be light you can get accused of not being able to take a joke.”

The subject clearly matters. She’s just made three shorts with a feminist subtext for Channel 4’s Comedy Blaps online series. “They’re called Temp,” she explains. They take aesthetic inspiration from the movies 9 to 5, Working Girl and Being John Malkovich. “It’s a cool idea. They’re the kind of things I used to do on TV in New Zealand.”

Matafeo is the third woman to win the Edinburgh Comedy Award for Best Show since 2013, so this is no longer a novelty. But she is the first person of mixed heritage to win with a solo show (Richard Ayoade was part of the Garth Marenghi group in 2001). Her father is Samoan, her mother Scottish-Croatian. Her parents are separated and her mother teaches in Uganda. They were supportive but there was little money around. “They said I could do whatever I wanted as long as it was cheap. They couldn’t afford ballet but comedy was free.”