We've lived in San Diego for 40 years and would generally consider Casa Guadalajara near Old Town on Taylor Street to be the city's best. Can be reached by bus or trolley to Old Town stop and then a short walk. There is usually a line after 5:30 but worth the wait. Patio dining is available and very pleasant. It is owned and managed by Diane Powers, the beautiful San Diego restauranteur who has developed many successful restaurants in the San Diego area.