I love the land's end cliff walk starting from here: https://goo.gl/maps/oUNxNPBDhWFhKUeM7. Accessible by bus. You can extend it by going down the coast, through Golden Gate Park and then end up at Haight St for food and lots of interesting stores. Not sure if that's considered touristy.
I still like visiting Chinatown when I get back that way. When I was a kid, dad always took me to the Golden Gate Fortune Cookie Factory, and I still stop there every time. Haven't lived in the Bay Area for almost 10 years now, though.
Avoid downtown. Spend time exploring the Mission, the Castro, Japantiwn, the Richmond district, the sunset district.
Fire up Google maps and go and explore the orange areas scattered around the city.
For a more specific recommendation: start at Arsicault bakery and then head down Clement St from there.