Since 2014, Roman chef and pizzaiolo Daniele Cason has been serving Roman-style pizza made from a blend of five organic Italian flours and 80 percent Italian water. The dough is fermented for 48 hours, resulting in a delicate and airy crust. The restaurant is on the 38th floor of the Mandarin Oriental hotel in the quiet Nihonbashi district. It has only eight seats at the marble countertop overlooking the open kitchen and pizza oven. Dinner is omakase-style with two seatings, and diners try eight different pizzas.