Alex Powar is talking chemistry — the chemistry of coffee. We're sipping espresso in Caledonia Alley, right behind San Francisco's Four Barrel Coffee, where Powar works as director of research and education. Originally a pre-med student back east, he encountered the coffee world through a training program while working in a Palo Alto restaurant. He now trains baristas and the public on how to make the best coffee possible.
Full disclosure: I'm a regular, and I'm really enjoying the espresso.