If you haven't visited El Serrano along Lancaster's Columbia Avenue lately, you haven't visited El Serrano. Or, perhaps it is more appropriate to say, you haven't visited Peru. Every square inch of the Latin-American restaurant has been extensively redesigned, upgraded and refurbished authentically, with architectural details similar to those of 150 years ago--to the point that stepping through its hand-carved mahogany doors is like entering a Peruvian hacienda. As owner Manuel Torres says, "it's like going on vacation."