One of the pleasant surprises about visiting San Francisco is that it has fantastic food. Not indigenous US food, but the food-culture imported by its immigrants from south of the border. Taquerias provides authentic, very tasty, cheap Mexican-style food to locals everywhere - especially in The Mission District. The best one is El Toro Taqueria on Valencia St. It is vegetarian-friendly (ie: it definitely doesn't cook beans in lard).
El Toro Taqueria: 598 Valencia St;
tel: (415) 431-2535;
Here's a photo: www.flickr.com/photos/bryceedwards/134769479/
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