San Diego's food scene is built on Mexican and seafood, with a serious craft beer culture surrounding both. Mexican food is the city's strength — given the border is twenty minutes south, the carne asada, fish tacos and Cali-style burritos here are among the best in the United States. Seek out the strip-mall taquerias of Barrio Logan, City Heights and National City; the touristy Old Town restaurants are fine but rarely the best in town.
Little Italy downtown is the upscale dining district — modern Italian, seafood, ramen — with a good Saturday farmers' market. North Park and South Park have the city's most interesting independent restaurants, particularly along 30th Street. La Jolla trends fine-dining and pricey; Pacific Beach is the casual beachfront spot for fish tacos and post-surf burritos.
For seafood, the Tuna Harbor Dockside Market on Saturdays is where the local fleet sells direct off the boats. The fish tacos at any halfway-decent taqueria are the affordable, ubiquitous option.