Tomato pie is a beloved specialty of Philadelphia. It resembles pizza, though Philadelphians know it to be different. In the early 1900s, bread bakers would take leftover bread and top it with “gravy” (red sauce) and a sprinkling of Parmesan cheese to save the dough from going to waste. The dish is ubiquitous in Philadelphia today, with many bakeries, like Sarcone’s Bakery in South Philly, serving it either hot from the oven or at room temperature. Insider’s Taryn Varricchio headed to Sarcone’s to learn why Philadelphians treasure tomato pie.