Robyn Goldman is making her special brand of ice cream from scratch -- using liquid nitrogen to freeze the ingredients in about a minute.
"We built this machine purely for reason of creating better ice cream and doing it right," said Goldman.
That's not the only unique thing about her business. A Radio Flyer wagon she pulled around the Financial District used to be her store. Now her store is a former shipping container customized for her business.
"We're building them offsite and we are able to drop them onto the site and connect them to utilities we've already connected in the ground," said architect Douglas Burnham.
The store - Smitten Ice Cream - is just the first of a dozen shipping container-based businesses set to occupy vacant lots in San Francisco's Hayes Valley neighborhood. It's part of a city redevelopment program.
"Hayes Valley is a very artisan part of San Francisco. It's up and coming, really creative and you know it was previously the old freeway and now it's come alive and really started to blossom," said Goldman.
"We see this as a new model of development. We call it a flexible urbanism. It's something that can that can respond to the pace of our contemporary culture, where things happen quickly, we're all on our mobile devices and engaging with all different content," said Burnham.
Six food businesses will share space with Smitten on the lot. The vacant lot will one day host a beer garden. There will also be an art gallery and nine pop-up retail businesses -- all in containers that are as easy to take down as put up. And taking them down is exactly what the city expects them to do at the end of their four year lease.
"It's sort of an interesting compromise between temporary and permanent. It's rethinking what a retail environment looks like and feels like," said Goldman.
It costs anywhere from $7,000 to $40,000 to fix up the containers and $2,000 to $5,000 a month to lease one. Smitten is open for business now, just in time for the warm up.