La Diferenca is definitely the place if you are only going to eat in Tijuana one night - lovely ambiance and wonderful food.
HACIENDA Cien Anos has been out of business for quite a while now.
There is another restaruant, Cien Anos, which is often confused with HACIENDA Cien Anos. In it's heyday, it was the best.
Depends on what you like to eat, Hungry Hiker's Guide to Tijuana - http://hungryhiker-tj.com will give you full scoop on Tijuana restaurants.
Hacienda Cien Anos: http://www.tijuanaonline.org/restaurants/cien/
La Differencia: http://www.tijuanaonline.org/restaurants/diferencia/
Sanborns at Plaza Rio Tijuana
Anotojitos La Poblana at Plaza Rio Tijuana
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