The director of The Arbor and The Selfish Giant returns to her favourite city for her new film. She talks about celebrating lives on the margins and how an ice-rink kiss changed her life

Would you like coffee?” Clio Barnard asks. “Is goat’s milk OK?” Ooh, that sounds exciting, I say. “There’s oat milk, too.” Barnard is scouring the fridge. “We’ve even got regular cow milk.” It’s early morning when I arrive at her house. Though, as she explains repeatedly, it’s not her house – she’s just renting it while working in London and Essex. It reminds me of Ali & Ava, her lovely new film. Every time Ali tells his friends that Ava is a teacher, she corrects him with “teaching assistant”. Details are important to Barnard.

“Right, would you like some breakfast?” She couldn’t be a warmer host. Then we sit down to talk, and suddenly she’s a bag of nerves. She loses her words, apologises for going blank, and looks to her producer Tracy O’Riordan for support. She eyes my recorder enviously. “I’d much rather be the person with the tape machine on the table asking you questions.” She pauses. “I’m quite a shy person, Simon.”