The line outside a frozen yogurt shop in downtown Manhattan would’ve been rather unremarkable in a city filled with trendy experiences, except for one detail. It was really cold.

“I was stunned to see people lining up in the winter to buy frozen yogurt,” said Howard Schultz, the former head of Starbucks.

Schultz, who is advising the company, liked what he saw that chilly day at Mimi’s, which had opened its first location the previous August. The 72-year-old billionaire is credited with changing how Americans think about coffee with better ingredients and more of a higher-end experience. He sees similarities in how Mimi’s is approaching fro-yo.

“She is in a commodity business like we were,” Schultz said of Amber Linz, Mimi’s twenty-something co-founder. She realised early on the need to build a premium brand, and she’s done a “very good job of elevating the experience”.

Mimi’s is part of a burgeoning renaissance of frozen yogurt, which includes other shops such as Birdie’s, Myka and Mythos, taking hold in New York and other parts of the US. These companies are winning over Generation Z with artisanal toppings like Italian-made pistachio sauce, vibey stores for hanging out, and a pitch that fro-yo is a healthy-ish treat. The approach is working, and they’ve persuaded fans to pay upwards of US$30 for their fro-yo bowl.

In the US, servings of frozen yogurt rose 26 per cent to about 87 million in the 12 months through March, according to researcher Circana. The trend is being driven by Gen Z, whose oldest members are in their late 20s, as they seek out healthier lifestyles. They are drinking less alcohol, exercising more and looking at food labels for nutritional value.

Fro-yo fills that need of wanting to indulge without attaching guilt, according to David Portalatin, a senior vice-president at Circana. The thinking goes: “I can have this treat and also feel like I’m making a better choice.”

Jenny Ammirati has seen the shift first-hand. When she co-founded Culture with her husband about 15 years ago in Brooklyn, customers asked about their yogurt’s fat content. Now they want to know if it’s probiotic, made from scratch and if the flavours are real, she said.

Ice cream does have more calories than frozen yogurt, but that can quickly be eroded with toppings. At Mimi’s, customers can add a mix of healthy and not-so-healthy options including fresh fruit, cookie dough and chocolate chips. Still, the appearance of being better for consumers is helping fro-yo’s resurgence.