When consumers in Shanghai pick up weekend snacks at Freshippo, Alibaba's upscale chain, they may notice black packages of Chen Shu brand sour and spicy instant noodles made of sweet potatoes from faraway Zhouzhai village in Guizhou province.

Tucked deep in the Wuling Mountains, Zhouzhai rests on steep slopes and rocky soil, which render most crop cultivation virtually impossible. Sweet potatoes are a rare exception. Originating in South America and now common in China, the potatoes became so abundant in Zhouzhai that farmers fed them to their pigs.

Under Party branch secretary Zhang Cheng's leadership, the tuber now serves as a sort of currency for residents. Each mu — 0.067 hectares — of sweet potatoes brings in about 3,000 yuan ($410.2).

Zhang, who is in his 50s, was the village's first vocational school graduate. He remembers the day when he left for Guiyang, the provincial capital, carrying a sack of sweet potatoes to eat. All across rural Guizhou, every household grew them. In those days, he said, families ate them at home or fed them to livestock, but hardly anyone dreamed of exchanging them for other goods.

After graduation, Zhang parlayed his technical skills into a cement business in Guiyang and lived a comfortable life. When he returned to Zhouzhai in 2016, he found his hometown still mired in poverty. This motivated him to lead major change.

For more than 20 years, Zhouzhai's young people had been migrating to cities for work, leaving old farmers and small children at home. The left-behind children faced mounting challenges in daily life and education. Seeing the need, Zhang donated more than 1.2 million yuan for relief and established a scholarship program for local students.

Even with policy support, however, poverty only eased; it didn't end. Zhang knew charity alone could not transform an entire community. With the concrete sector cooling, he returned to his roots for an answer, which he found in the humble sweet potato.

Because potatoes can withstand droughts and floods, they are a reliable crop. That is one reason Zhang chose them to help lift the people of Zhouzhai out of poverty.

The village had opened a government-backed sweet potato noodle processing facility back in 2016, but it failed due to a lack of good branding and sales channels. In just two years, it had accumulated a collective debt of 680,000 yuan.

Zhang conducted a year of market research and invested more than 45 million yuan in 2018 to build a modern starch and sweet potato flour factory in the village. He installed the country's most advanced production lines, registered the Chen Shu brand and put people to work.

Focusing mainly on young consumers who love spicy and sour noodle cups made from pure sweet potato starch, the company grew to produce 40 different products.

It converts 150,000 tons of fresh tubers a year into 25,000 tons of starch and 12,000 tons of noodles, which are then transformed into 100 million cups of spicy and sour noodles. The company has become Guizhou's largest sweet potato processor.

Last year was pivotal for Chen Shu. One of China's major snack brands was criticized online for having no real sweet potato content in its so-called sweet potato noodles. Virtually overnight, viral images of trucks piled high with Guizhou tubers outside the Chen Shu plant turned the company's "100 percent sweet potato" claim into its loudest advertisement. Annual revenue jumped from 340 million yuan in 2023 to 710 million yuan in 2024. Zhang aims to earn 1 billion yuan by the end of this year.

The booming sales have changed people's lives in Zhouzhai. For instance, in the family of Zhang Zhudong, six migrant workers returned in 2018 to join the company. Last year, they earned more than 400,000 yuan in wages, according to the local government.

This year, the company has contracts for 130,000 mu of sweet potatoes. At 3,000 yuan per mu, the crop will bring tens of millions of yuan to local farmers. The factory also provides more than 700 steady jobs, mainly for local women and returning young people, at an average monthly income of more than 4,300 yuan.

Last year, residents earned 1.8 million yuan in wages, pushing per capita disposable income to 28,000 yuan — more than two and a half times what it was in 2018, according to township government data.

To stay ahead of the changing trends and adapt to consumers' tastes, Zhang established an R&D center in Shenzhen where he can track new trends and hire top talent. He will soon launch a Luosifen noodle product based on sweet potato starch noodles that promises a chewier and more elastic bite than traditional rice noodles.

Since taking charge of the company and being elected Party branch secretary of Zhouzhai in March 2022, Zhang has overseen every facet of village life.

At 8 pm on the last Saturday of each month, he and other cadres host a village meeting via livestream on Douyin. Migrant workers and the elderly at home tune in to hear new policies, safety advice and development plans, and they can ask questions in real time. These online gatherings draw village leaders and consumers from all across the country.

After each hourlong meeting, Zhang sticks around to sell farm goods from Zhouzhai.

"Convenience foods still hold huge promise," Zhang said. "I come from the countryside, and I believe I can lead more of my neighbors to better lives."