Oh, pizza. Is there a single food more universally beloved that is also so incredibly divisive? The most contentious of these divisions comes between New Yorkers and their New York-style slices and Chicagoans and their deep dish pies. Deep dish pizza was invented in the Windy City in 1943 by Ike Sewell, founder of Uno’s Pizzeria. It became so popular that it spun into a huge national chain and inspired dozens upon dozens of other deep dish pizzerias in major cities across the world. So tuck a napkin into your collar, grab a fork and knife (you’ll need them), and celebrate National Deep Dish Pizza Day with us this April 5!