Zhang described the criticism as too "old fashioned".

Zhang said one of his main inspirations is Jiro Ono, an 89-year-old Japanese sushi chef who runs a tiny, 10-seat restaurant located inside a Tokyo subway station.

Despite its humble appearance, the restaurant has received a prestigious three-star Michelin Guide rating, and diners from across the globe make reservations months in advance to guarantee a seat.

"It's his devotion to food that earns him respect, no less than those involved with the so-called glamorous jobs, such as bank clerks, fashion designers or architects," Zhang said.

"This reaffirms my belief that every job is decent. As long as you put your heart into it, you will be satisfied with your work."

Zhang opened his noodle shop with the help of three friends in April. He used most of his savings to pay for the rent. The restaurant's specialty is mifen, or rice noodles. Zhang learned how to cook the dish from a mifen master in Changde.

On a recent morning, Zhang arrived at the shop around 7. He started the workday by boiling water and cooking noodles. After working for 15 hours nonstop, Zhang began preparing food for the next day.

"I usually leave the shop around 10 pm, when the bustling CBD is quiet," he said.

Zhang opened the store on April 8. That day, he sold 5,430 yuan ($876) worth of noodles. The next day, his sales increased to 6,530 yuan, eventually reaching 9,700 yuan a few days later.

Zhang said he was "astounded" and "shocked" by his success. "I never thought a noodle shop could be this profitable."

However, Zhang has no time to bask in his good fortune. "We are so busy and have to cook a lot of noodles and beef every day," he said. "We want to provide the authentic taste of Changde mifen to people in Beijing."

Zhang said he likes to talk to his customers to get feedback and suggestions. "We want the business to do well, but guaranteeing quality is more important," he said.

Customers dining at Zhang's noodle shop must make reservations in advance, as his restaurant can only serve 120 people a day. Customers are encouraged to clean up after themselves, and those who recycle are rewarded with some fruit to promote a green lifestyle. "We want to prove that jobs are not divided by grades and ranks, and as long as you are devoted, you can be artistic and gain full respect from society," he said.