When Ms. Young saw these familiar streets empty out at the start of the Covid-19 pandemic in 2020, she sensed that a way of life she had taken for granted was suddenly under threat. Misinformation about Asian-Americans carrying the virus hit Chinese businesses especially hard. “Waiters were just standing around, businesses were losing up to 80% of their customers,” she recalls over a stir fry of cauliflower and snow peas at the Mee Sum Café on Pell Street, amid the thrum of preparations for the Chinese New Year celebration, which runs through Feb. 5. “I realized I hadn’t truly appreciated how much Chinatown means to me.”

Usually shy, Ms. Young has become a forceful advocate for New York’s Chinatown. She insists that its multigenerational mom-and-pop shops are an essential part of the American story: “So many of these entrepreneurs had come to this country with nothing, and through sheer grit and hard work had realized the American dream.” Since early 2020 she has broadcast video interviews with local business owners and raised money to buy meals from Chinatown restaurants and deliver them to those in need, among other efforts. Her work preserving and sharing Chinese culinary traditions earned her a Julia Child Award and the James Beard Humanitarian of the Year Award last year.

“I had no idea there was an activist heart in my being,” says Ms. Young. “But I realized somewhere in the pandemic that as a Cantonese culinary historian who was comfortable with the media, I had just the right qualities to be a voice for the voiceless.”

Although her parents took pride in making traditional Cantonese stir fries and soups for their two children, Ms. Young says she discovered her love of cooking from Julia Child. At an early age she began watching “The French Chef” on television and was soon sending self-addressed envelopes to WGBH to get copies of the recipe each week. “I just loved her way of being,” Ms. Young recalls. She was mesmerized by Child’s informality and unflappability as she expertly cooked—and occasionally fumbled—exotic French dishes: “I wanted to be just like her.”

Ms. Young vividly recalls the day her mother let her make Child’s recipe for brioche. “They were just gorgeous, golden and puffed, and the aroma that hit us of pure butter was insane,” she says. “It made me realize that I wanted to cook another recipe, and another.” She convinced her father to take her to a local book-signing event featuring Child, where they were the only Asians and she was the lone child. “It never occurred to me that it meant we didn’t belong,” Ms. Young recalls. Her signed copy of “The French Chef Cookbook,” along with her family’s wok and fine china, are now in the collection of the Smithsonian’s National Museum of American History, where she serves on the advisory board for food history programs.

At 13, Ms. Young persuaded Josephine Araldo, a cook and teacher in San Francisco, to let her sit in on some French cooking classes in exchange for washing dishes and other odd jobs: “That was ballsy, now that I think about it!” she says. A high school internship with recipe developer and food stylist Stevie Bass turned into a regular job through college. “It was life-changing,” she recalls. “I just loved testing recipes like a lab experiment.”

In 1979, Ms. Young headed to New York for a job in the test kitchen at General Foods. She assumed she would return to San Francisco after a year but fell in love with the dynamism of New York City and liked living at a remove from her parents’ scrutiny and expectations. “My mother saw working in the kitchen as a lowly job,” she explains. “They wanted me to be a concert pianist or a doctor.”

She went on to work for Rebus, a book-packaging company that produced cookbooks for Time Life Books. In her 30s, she realized that while she had helped create more than 40 cookbooks, she didn’t know how to make the dishes that tasted of home. “A lot of the comfort foods I’d grown up with I’d never taken the time to learn,” she says. “I knew if I recorded all of my parents’ recipes, it would be a gift I could give my family and the next generation.”

It took some cajoling to get her parents on board: “My mother would cook a dish, and I would say, ‘I don’t remember it tasting like this as a child,’ and she would say, ‘The real dish takes too much time, you don’t have time for that.’” Yet what began as a recipe book became a kind of memoir as talking about food encouraged her parents to finally open up about their past, like the fact that her father had owned a Chinatown restaurant in the 1940s. “It was really an amazing way to learn not only my family’s recipes, but also my family’s story,” she says. “The Wisdom of the Chinese Kitchen” (1999) launched Ms. Young’s work in preserving and sustaining Chinese American culinary traditions. Other books followed, including “The Breath of a Wok” (2004) and “Stir-Frying to the Sky’s Edge” (2010).

Grace Young prepares a vegetable stir-fry in her kitchen at home. Jingyu Lin for The Wall Street Journal

Although Ms. Young didn’t start cooking regularly with a wok until she was in her 30s, she has earned some renown as a wok evangelist, eager to demystify the traditional Asian pan for home cooks. “People call it a stir fry pan, but it’s so much more. You can steam, boil, poach, pan fry, braise, smoke. I use my wok to scramble eggs, spatchcock chicken and pop corn,” she says. When she travels she always packs her wok in her carry-on, and she owns too many to count. “They all tell a different story,” she says.

Outside the cafe on Pell Street, Chinatown seems to be back to its bustling self. Yet Ms. Young notes that the pandemic claimed scores of long-established Chinatown businesses in New York and around the country. “Chinatowns across America are all reporting reduced foot traffic, less tourism, increased burglaries and vandalism and a dramatic drop in traffic at night, and that is because of anti-Asian hate crimes,” she says. “A lot of businesses let employees go home early for safety reasons, and locals don’t feel safe coming out at night.”

Before the pandemic, when people asked Ms. Young what her favorite Chinatown restaurant was, she would encourage them to cook at home. “I’m a cookbook author! I want people to cook from my books!” she explains. “But I realized if these restaurants don’t survive, Chinatown won’t survive.” This year, instead of laying out a large meal of home-cooked Cantonese dishes for her husband and friends, she is celebrating the Chinese New Year with a feast of food from various local restaurants: “I’ve never eaten so much takeout in my entire life.”