The chicken cheesesteak is the cheesesteak with the protein swapped and the method left untouched, and the method is the sandwich. Chopped chicken instead of ribeye does not make this a chicken sandwich on a roll: it is still decided on a flat-top griddle in about a minute and a half, still finished by melting cheese into the meat while it is on the steel, and still folded into a long roll built to carry a heavy fused filling. What changes is what the swap costs and what it gains.
The craft is in compensating for a leaner protein. Ribeye brings its own fat to the griddle and stays tender almost regardless; boneless chicken thigh or breast is drier and easier to overcook into rope, so it has to be chopped fast on the steel and pulled the moment it is done, with the cheese going on immediately to lock in moisture before the meat tightens. Cheez Whiz, sliced provolone, or American is still the standing choice, and it does more work here than on the beef version, because there is less rendered fat in the pile and the cheese is carrying more of the richness. Fried onions cooked down on the same steel matter for the same reason: they put back the sweetness and moisture the lighter protein does not supply on its own. The long Philadelphia roll, tender inside and structured enough at the crust to hold a molten filling without tearing or dissolving, plays exactly the part it plays on the beef cheesesteak. The whole thing is still engineered to be assembled, handed over the counter, and eaten before the center sets.
It carries the same ordering grammar as its parent: wit or witout for onions, and a cheese call that is its own standing argument. The pizza, pepper, and mushroom builds change a different variable on the same griddle and deserve their own articles rather than being crowded in here.