Converting or infecting? Either way, non-chain versions of deep- dish is are spreading beyond Chicago. Such is the pizza mystery that the style landed in St. Louis, where Pi Pizzeria (area code 314, get it?) launched its self-described “irrationally delicious deep- dish and thin cornmeal crust pizza,” launched introduced St. Louis' first food truck (they claim), supposedly became the best pizza President Obama has ever had, and has since become a successful mini-chain of its own (there are four other St. Louis spots and offshoots in Washington, D.C., and Cincinnati). That’s right, St. Louis-spawned Chicago-style pizza... in D.C.
There are 12 standards (six each of deep- dish and thin crust). Beyond topping standards like sausage and pepperoni, Pi offers zucchini, feta, prosciutto, gorgonzola, and goat cheese (they also do gluten-free thin crusts and have vegan cheese; can that really be called "pizza" [(wink])? Thin-crust purists whose blood is already boiling over the fact that Pi proudly declares, “Sauce = On top” ought look away from the signature deep-dish, The Delmar, topped with mozzarella, chicken, red and green peppers, red onion, fresh cilantro, Cheddar, and… barbecue sauce.
— Arthur Bovino, 101 Best Pizzas in America 2015, 8/6/2015