“I make carrot ginger soup. I make dumplings,” says Mao, the 71-year-old owner of David’s Dumplings and Noodle Bar in the Hillsborough Street district of Raleigh.

But ask his next-door neighbor of 40 years, N.C. State Professor Emeritus of Chemical and Biomolecular Engineering, Dr. Hal Hopfenberg, and you’ll get a more profound story. “David has taught me what it means to be loyal, what it means to be brave,” he says. “And of course, how to cook dumplings."

The two met in 1966, half a world away. Hopfenberg, originally from New York, was deployed during the Vietnam War to Cholon, a small town outside of Ho Chi Minh City (formerly Saigon), Vietnam. This is where Mao, the youngest of 13 siblings, worked at his family’s restaurant, The Eskimo, and first met Hopfenberg as a customer.

But what began as an ordinary meal became much bigger than either of them could have imagined. Hal began frequenting David’s restaurant, and the two became fast friends. They struck a deal: Hal would teach David math, and David would teach Hal to cook.

Their friendship seemed improbable. Hal, an MIT doctoral graduate, was a young Army Captain developing technology for soldiers; David dropped out of school when he was 16 in order to run the family restaurant and faced daily prejudice against his Chinese ethnicity.

The political and economic climate in Vietnam was fraught.

“It was tough [in Vietnam],” David said. “I would sleep on the floor of my restaurant. I would clean the floor, cover it with a mat and sleep on the floor. It was tough, but I had no other choice.”

But, after meeting Hal, David finally saw his “now or never” chance. As Hal’s return to the United States drew nearer, David approached him and asked about going along. Hal agreed to help him immigrate to America.

“I thought I owed it to him,” Hal explained. “It was a symbol of what our friendship was about.”

Hal departed back to the United States in December of 1966 to a new destination—North Carolina — to start his career at NC State University. He had only visited the state for one day prior to his deployment, and although unfamiliar with the area he quickly and surprisingly became enamored with the region. “I loved it,” he said. “I wasn’t prepared to love it.”

Once settled into his new home, Hal spent six years working to get David’s visa and residency approved. Finally, David, then 28-years-old, arrived in the United States in 1972 with just a few hundred dollars and a dream to open his very own restaurant. 

David initially faced trouble adjusting to American culture. “Life is so different [in the United States],” he said. “It’s two different worlds. When I saw a gas stove here for the first time, I couldn’t believe it.” 

Hal supported David during his transition to life in North Carolina. He helped with English lessons, business advice and American cooking techniques. David lived with him for three years while working in different restaurants, including French, Italian and Greek, learning how to combine ethnic cooking with American styles. 

David returned to Vietnam in 1973 to bring his wife, Quyen, to America, and upon their return, bought the house right next door to the Hopfenberg family in 1975, where they’ve remained as neighbors and friends for the last 40 years. The families share a love of Wolfpack sports, culinary adventures and porch talks. 

Hal and his wife, Patsy, have also helped support David and Quyen’s son, David Mao Jr., 36, who was born in Raleigh.

“They treat me like a son,” said David Jr.,  who learned to speak English with help of the Hopfenbergs.  He sees his father, David, and Hal's friendship as a “Godsend.”

“If it wasn’t for Hal and his family, we wouldn’t be in the United States, and my dad wouldn’t have his restaurant.”

David opened his first restaurant, The Mandarin House, in September of 1976, and since then, has owned seven different restaurants, including his current operation, which opened in 2010.

David works 10 hours a day, every day; he’s lost count of the number of dumplings he’s made. “In the restaurant business, you either hate it or love it. This is my profession. I guess I love it,” David said. “People say it’s the American Dream. I guess that’s true.” 

“It’s like seeing your son succeed — watching his courage,” Hal agrees. “Can you imagine going into a whole new culture, and then becoming a part of it?”

Although Hal is not financially involved in David's restaurant, the two often confide in each other, whether it’s about mowing the lawn or taking out a business loan. “He always gives me good advice, and he always looks after me,” Mao said. “He is closer than a brother. If you have a good friend, you only need one.” 

Hal returns the sentiment. He’s watched Mao grow from a young U.S. immigrant to a seasoned and successful entrepreneur, all while maintaining his kindness, dedication and friendship that is so dear to Hal. “From my perspective, the giving has always been from him to me,” he said. 

The pair's friendship continues to stand the test of time. Over the last four decades, each has built a career and raised a family.  And although neither could have predicted this enduring friendship, both agree that their lives would be drastically different, if it hadn’t been for the chance meeting in Vietnam 49 years ago. 

"It's been the spine of our lives," Hal said of their friendship. "If we had never met, it would be a different life, but it wouldn't be a better life."