San Francisco (CNN) -- "Are you open yet?" a passerby asked. It was 10 a.m. on a sunny fall day here, where a small group of staffers met a CNN camera crew outside of Smitten Ice Cream.
By the time the doors officially opened two hours later, a handful of others had inquired about when they could get a scoop. The people wanted their ice cream.
You see, this is not your typical ice cream parlor.
"Here at Smitten we actually make every single batch of ice cream to order," explained store founder Robyn Sue Fisher. "So nothing is frozen until you order it, and we make everything from scratch that morning."
Using seasonal and local ingredients, Fisher's team creates creative flavors like cinnamon apple crisp, maple brown sugar squash and Meyer lemon gingersnap. Smitten doesn't use preservatives, emulsifiers or stabilizers in any of its ingredients.
And because its creations are frozen before your eyes in seconds, the process involves some serious science.
"We do get super nerdy about our ice cream and we get nerdy because we think it makes a better product," said Fisher.
After a few years in the corporate world and attending the Stanford Graduate School of Business, Fisher decided to follow a childhood dream.
"My mom used to tell me that I had two stomachs and one of those was solely reserved for ice cream," Fisher said.
So the little girl with the big appetite invested her life savings, teamed up with some engineers and spent five years prototyping ice cream machines in her backyard. The final product was a high-tech, patented mixer called a Brrr machine. Those who serve the silky smooth ice cream at Smitten are aptly named, Brrristas.
Each order takes about 90 seconds to make and many customers took full advantage of that wait by snapping pictures and videos of the Brrr machine in action. Brrristas pour in organic cream along with other ingredients and set the Brrr in motion. It whirrs and spins and the mixing bowls become surrounded by a fog of evaporating liquid nitrogen.
"We use nitrogen because it's super, super cold. It's actually negative 321 degrees Fahrenheit," explained Fisher, "And a super, super cold freezing process actually has the ability to make a smaller ice crystal, and a smaller ice crystal means a really, really smooth product."
One of three different patents for the Brr machine is a double-helical beater that's designed to scrape every surface of itself and every surface of the bowl to develop the tiny ice crystals. It also has "smart" software that's programmed to know when the ice cream is ready to be served.
"A smaller ice crystal makes a smoother, more luscious texture," said Fisher, "so our ice cream is actually a lot creamier than other ice cream in addition to being a lot more fresh."
But before the brick-and-mortar store and the frenzy of foodie fans, Fisher had to hit the streets to dish out her treats. She rigged up a Radio Flyer wagon with a battery pack to power the Brrr and tweeted her location for the day.
"I was totally broke and that's why the only thing I could do was sell ice cream out of a Radio Flyer wagon -- which was a super amazing way to learn about what people wanted," said Fisher.
"I tested a bunch of different flavors and I already had teamed up with our amazing chef, Robyn Lenzi, and so she made a different flavor every day. I'd pick it out at her house and go into the street."
The combination of fresh ingredients, the magic of the mixer, and word-of-mouth proved to be a winning combination.
"This past summer we served over 20,000 people a month out of this tiny little 320-square-foot shop, so that's a pretty good number for us," Fisher said.
Smitten plans to open up three new locations in the San Francisco area within the next year.
"We're keeping it local, but we're going to be spreading the Smitten love," Fisher said.