“Yes, I’d like to order 4,000 lattes to go, please,” Jobs said, grinning. “No, just kidding. Wrong number. Goodbye!”

As Jobs hung up, a large crowd in front of him erupted in laughter. That’s because this wasn’t some private prank call. Jobs was on stage at the Moscone Center, where he had just unveiled the iPhone to the world. His call to the Starbucks that day was the first real public phone call made from an iPhone in history. Sure, Jobs had held a conference chat earlier in his presentation with Apple executives Jony Ive and Phil Schiller–but that call was prearranged and heavily scripted, no different than the dozens if not hundreds of calls they would’ve made during rehearsals, or the likely thousands of calls performed while testing the device prior to its announcement. (Ive and Schiller were even in the Moscone Center audience that day, cupping their phones to block Jobs’s loud voice from interfering with the call.)

The true test of the iPhone’s power came when Jobs opened Google Maps, and–to the awe of those in the auditorium–searched for Starbucks and called up a nearby store, seemingly on a whim. It foreshadowed a revolution in the mobile world, not just for consumers but also businesses. It was only appropriate that Jobs would call Starbucks, a company that’s been transformed by the tools Apple has created or given way to, from processing 100 million mobile payments through its app to partnering with Square to handle its credit- and debit-card transactions. But for Starbucks employee Zhang, there was no way of knowing a smartphone revolution was on the horizon. To her that day six years ago, it was just another prank phone call. Little did she know it was from Steve Jobs.

With help from Starbucks, Fast Company was able to track down Zhang, a soft-spoken barista who goes by “Hannah.” Sincere and sweet, Hannah has been working at the same Starbucks for more than a half-decade. “Honestly, I was shocked,” she recalls. “I have never heard somebody order 4,000 lattes to go. I didn’t say anything because I was shocked. But my first impression was that he was just being humorous. He sounded like a gentleman.” (The exchange takes place at the five-minute mark in the video below.)

Hannah, who was all smiles when we caught up with her recently at the same Starbucks location, only learned afterward that it was Jobs who had placed the impossible order. She first found out from customers making a pilgrimage to the location, and now feels a sense of pride that the Apple cofounder chose her store. “Customers would sometimes come up to me and go, ‘Did you know somebody at your store actually talked to Steve Jobs?’ I feel very happy and lucky that I had a chance to actually talk to him. It means a lot to me that he picked our Starbucks,” explains Hannah, wearing her green Starbucks apron. “My friends were surprised and jealous, like, ‘Wow, you got a chance to talk to Steve Jobs?’ They say to me, ‘You should’ve said more! You just say Good morning and How can I help you.'”