tortillas made for use with mushu. Mushu purists do not always react positively to this trend. In addition, many restaurants serving more native-style Chinese cuisines exist, due to the high numbers and proportion of ethnic Chinese in the San Francisco Bay Area. Restaurants specializing in Cantonese, Sichuanese, Hunanese, Northern Chinese, Shanghainese, Taiwanese, and Hong Kong traditions are widely available, as are more specialized restaurants such as seafood restaurants, Hong Kong-style diners and cafes, also known as Cha chaan teng (), dim sum teahouses, and hot pot restaurants. Many Chinatown areas also feature Chinese bakeries, boba milk tea shops, roasted meat, vegetarian cuisine, and specialized dessert shops. Chop suey is not widely available in San Francisco, and the area's chow mein is different from Midwestern chow mein. Boston Chinese cuisine in Boston results from a combination of economic and regional factors, in association with the wide Chinese academic scene. The growing Boston Chinatown accommodates Chinese-owned bus lines shuttling an increasing number of passengers to and from the numerous Chinatowns in New York City, and this has led to some exchange between Boston Chinese cuisine and that in New York. A large immigrant Fujianese immigrant population has made a home in Boston, leading to Fuzhou cuisine being readily available there. An increasing Vietnamese population has also had an influence on Chinese cuisine in Greater Boston. In addition, innovative dishes incorporating chow mein and chop suey as well as locally farmed produce and regionally procured seafood are found in Chinese as well as non-Chinese food in and around Boston. The selection of Chinese bakery products has increased markedly in the 21st century, although the range of choices in New York City remains supreme. Joyce Chen introduced northern Chinese (Mandarin) and Shanghainese dishes to Boston in the 1950s, including Peking duck, moo shu pork, hot and sour soup, and potstickers, which she called "Peking Ravioli" or "Ravs". Her restaurants would be frequented by early pioneers of the ARPANET, as well as celebrities such as John Kenneth Galbraith, James Beard, Julia Child, Henry Kissinger, Beverly Sills, and Danny Kaye. A former Harvard University president called her eating establishment "not merely a restaurant, but a cultural exchange center". In addition, her single-season PBS national television series Joyce Chen Cooks popularized some dishes which could be made at home, and she often encouraged using substitute ingredients when necessary. Philadelphia The evolving American Chinese cuisine scene in Philadelphia