This ' phở cải lương' failed to enter the mainstream. In the late 1920s, various vendors experimented with húng lìu, sesame oil, tofu, and even Lethocerus indicus extract ( cà cuống). Gánh phở declined in number around 1936–1946 in favor of stationary eateries. Around 1925, a Vân Cù villager named Vạn opened the first 'Nam Định style' pho stand in Hanoi. They were joined in 1918 by two more on Quạt Row and Đồng Row. Hanoi's first two fixed pho stands were a Vietnamese-owned Cát Tường on Cầu Gỗ Street and a Chinese-owned stand in front of Bờ Hồ tram stop.

They kept their heads warm with distinctive felt hats called mũ phở. The heavy gánh was always shouldered by men.

From the pole hung two wooden cabinets, one housing a cauldron over a wood fire, the other storing noodles, spices, cookware, and space to prepare a bowl of pho. Pho was originally sold at dawn and dusk by itinerant street vendors, who shouldered mobile kitchens on carrying poles ( gánh phở). The demand for this dish was initially the greatest with workers from the provinces of Yunnan and Guangdong, who had an affinity for the dish due to its similarities to that of their homeland, which eventually popularized and familiarized this dish with the general population. These include improved availability of beef due to French demand, which in turn produced beef bones that were purchased by Chinese workers to make into a dish similar to pho called ngưu nhục phấn. Ĭultural historian and researcher Trịnh Quang Dũng believes that the popularization and origins of modern pho stemmed from the intersection of several historical and cultural factors in the early 20th century. The traditional home of pho is reputed to be the villages of Vân Cù and Dao Cù (or Giao Cù) in Đông Xuân commune, Nam Trực District, Nam Định Province. The modern form emerged between 19 in northern Vietnam, southeast of Hanoi in Nam Định Province, then a substantial textile market. For example, villagers in Vân Cù say they ate pho long before the French colonial period. Pho likely evolved from similar noodle dishes.

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