There are various versions of this recipe on zaar, but this one is my favorite. The key ingredient is the chili sauce, preferably Heinz. In Pittsburgh, Isaly's "chipped chopped" ham is the brand of choice but it is hard to find outside of western Pennsylvania. The best alternative is to have the butcher slice the ham very thin (almost like shaving it), and then chop all those slices coarsely. These sandwiches are a hot and sweet treat with a little spice and a Pittsburgh favorite. I got it from a local Pittsburgh cookbook.