"The bakery still uses the same recipe developed by Louis's great-grandmother. In typical nonna fashion, she had a small kitchen in the back of the bakery where she would simmer the gravy (it's always called gravy around these parts), top her round tomato pies, and place them in the bakery's window. But the pie has evolved over the years from that round form into a rectangular affair. "It was basically what people were asking for," Sarcone says of the shape shift. "Most pizza parlors that came to America, they were making the traditional round pie."

Read the rest on Eater Philly.