10th Annual Northern California Soy and Tofu Festival (SF) 10th annual Northern California Soy and Tofu Festival returns July 2  After a two-year hiatus, the Northern California Soy and Tofu Festival, a celebration of the joy of soy, returns Saturday, July 2, from 11 a.m. to 5 p.m., to San Francisco’s Japantown. For the first time ...