> A pizza 2 inches deep? Surely there is another name for such a meal.
Yes, it's a tourist trap meal. We here in Chicago really do like deep-dish pizza, but many of the more famous brands exaggerate the thickness because it seems as though tourists prefer it that way. A typical Chicago resident isn't going to buy one like this more than once every few years, unless they have visitors that insist on it.
You eat it with a fork and knife. Despite the huge amount of cheese and sauce, a good one will have a really crunchy crust and it should be so good that you consider it one of the best parts of the pizza.
The flavor/preparation/ingredients are what make a good Chicago-style pizza and not the thickness. In more residential areas, you'll have pizza shops where the deep dish pizza is no more than 1 inch, which is really what a Chicago resident buys for themselves (but the thin crust is most definitely purchased more frequently).
As far as I can tell [Chicago-style | deep dish] pizza[1] is uniquely specific in describing such a preparation. No obvious alternative Pie-, Tart-, or Flan-based descriptor showed up when casually searching.