433 Valley Ave.
A post on Chowhound.com calls these some of the best real tacos in town, with authentic fillings such as carnitas (twice-cooked pork), cabeza (beef head meat/cheeks), tripe and lengua (tongue). They have a little bar for dressing your tacos, with diced onion, minced cilantro and several different kinds of salsa. City Scene (January 2009) says, "Arguably the best taco in town, served in house-made tortillas. Dress them at a bar that includes onions, cilantro, jalapenos, radishes and six kinds of salsas. Carnitas, sold weekends, are spectacular. Pork belly lovers shouldn't miss the cueritos."