Pizza professor Tony Gemignani has a new focus of study: Chicago-style deep-dish pizza. The differences between his deep-dish, stuffed and cast-iron pan pies can be so subtle that the waiters can't describe them, and the restaurant is cash-only. But the stuffed-crust pizza we ate there faithfully represented tradition, while adding a few tweaks–lard in the crust, more flavorful cheese in the center–to improve on the original. (See our previous coverage.)