Despite the downtown sushi restaurant that has reimagined the cheesesteak as an egg roll stuffing, and the close approximations of cheesesteaks assembled at both Vietnamese banh mi parlors and a Jewish delicatessen in the deep Valley, the basic form of the Philadelphia cheesesteak is well-settled. There will be a light, chewy Italian roll, almost certainly imported from the Amoroso bakery in Philadelphia itself; there will be onions; and there will be thin, griddled shavings of the cheapest imaginable beef. There will be a choice of available cheeses, including white American, hot Cheez Whiz and sharp provolone, although it will have melted completely into the meat before you have the chance to take a bite. It is not strictly necessary for a cheesesteak emporium to have birch beer, Tastykakes or a poster of the 1980 Phillies, but it is never a bad thing — extra points for an autographed photo of Tug McGraw. South Street and the Philly's Best chain both serve pretty decent cheesesteaks. Fredo's, a specialist in Pasadena, made exemplary cheesesteaks until the proprietor left in August. (They're still very good.) Philly West, an Eagles-centric dive bar near Westwood, may chop their meat a little too finely, but they've mastered the proper ratio of onions to steak, and of chomp to goo. But for the love of God, ask them to hold the tomato sauce.