William Joo is the chef and co-owner of Pizzeria Sei, an acclaimed Los Angeles restaurant known for its delicate, Tokyo-style Neapolitan pizzas and experimental pizza omakase pop-ups. His approach draws on his South Korean heritage and experience working at some of the city’s most respected Italian restaurants.
Born in South Korea and raised in Los Angeles, Joo is a lifelong pizza lover who began seriously refining his dough while working at Daniele Uditi’s Pizzana and Daniel Cutler’s Ronan. He also staged at Michael Cimarusti’s Providence for a year and a half and worked under Gino Angelini at Angelini Osteria for five years. Although Joo has never trained in Tokyo or taken a purist approach to pizza-making, his trips to Italy and Japan continue to inform his evolving approach to pizza and cooking.
Joo and his wife, Jennifer So, opened Pizzeria Sei in 2022 in a compact Pico-Robertson storefront with limited seating. In June 2026, the couple expanded with a new flagship in Palms, where Joo serves Neapolitan, fried montanara, and Roman-style scrocchiarella pizzas in a full-service dining room with an expanded beverage program. The original location is now called Sei Pizza Bar and continues to specialize in the Tokyo-style Neapolitan pizzas that established Joo’s reputation.
Since 2024, 50 Top Pizza has ranked Pizzeria Sei among the best pizzerias in the country and the world. In 2026, the organization placed it at No. 2 in the United States. The restaurant is also included in the Michelin Guide and has received recognition from the Los Angeles Times and The New York Times.
