Sarah Adams, a teacher, started a side business selling her Jamaican grandmother’s rum cake in 2015 with $5,000 from her husband’s retirement savings. Soon, she was handing out samples at markets and street festivals, building her company, Ms. Macs, one tin at a time.

But when the pandemic crippled her growing business in 2020, Ms. Adams, who lives in a public housing complex in northern Manhattan, was forced to pivot. Teaching remotely, Ms. Adams put the money that she saved by not commuting toward trying out recipes for vegan muffins, reduced-sugar cookies and low-carb pizzas.

A few months ago, Ms. Adams received a newsletter from her landlord, the New York City Housing Authority, which announced a new competition for entrepreneurs living in public housing. It offered cash prizes of up to $20,000 and free business development classes.

“I thought it was fake,” Ms. Adams said. She called the housing authority to make sure it was real.

Ms. Adams, 47, owns one of the nine businesses that won “NYC Boss Up,” a “Shark Tank” style competition that invites some of the city’s poorest residents to propose business ideas for further development and funding. A total of 279 applications were submitted, of which 23 were selected for the final round. Those entrepreneurs went on to pitch their business plans and field questions from a panel of judges at the Central Library in Brooklyn in March.

The Boss Up program was funded for five years with a $1 million grant from the family foundation of Ron Moelis, a real estate developer who got the idea after reading a 2022 report by the Center for an Urban Future, a nonprofit. The report highlighted an untapped opportunity to increase entrepreneurship among public housing residents.

“It’s really hard to start a business in New York City,” said Mr. Moelis who, following the selection of the winning entrepreneurs, met with the losing finalists to offer feedback and encourage them to try again next year.

Mr. Moelis helped develop the Boss Up program with NYCHA, which provides free business programs to residents, and other partners, including FJC, a foundation that administered the award payments.

Applicants to the Boss Up program must live in one of NYCHA’s developments — which house about 368,000 residents citywide — or receive federal rent subsidies through its Section 8 program. The one-time awards are not factored into a family’s income, which is used to calculate their rent.

One of the winners, Valeria Ortiz Martinez, 18, who lives in the Dyckman Houses in Inwood, spotted a flier for the competition in her lobby. She has turned her idea for a customizable digital business card — which looks like a credit card and transfers information by being tapped on a cellphone — into a business, ConnectoTap.

Other winners, like Ms. Adams, were already running small businesses, but needed some help getting to the next level. She plans to use the $20,000 to introduce her line of healthier baked items and to focus more on marketing.

Kat Perez, another winner, started her business, Kat D Productions, in 2019 with video equipment borrowed from her alma mater, the College of Mount Saint Vincent, which was also her first client. While attending there, Ms. Perez and a friend made two videos of students defining slang terms. The videos together drew more than six million views.

Since then, Ms. Perez has shot more than 50 videos and last year earned $38,300 in revenue. “I felt like I finally had the foundations for my business to grow, but I didn’t have the capital or the resources,” said Ms. Perez, 25, who lives with her mother in the Bronx.

With the prize money, Ms. Perez plans to hire an assistant, buy additional video equipment and market her company on social media, she said.

Daniel Wool, who founded the company, Digital Design Truested Technologies, in 2022, plans to use the $20,000 to diversify and market his company, which pays volunteers to test hardware and software systems for companies. “It was a seed of a business — I think they really gave me the impetus to go forward,” said Mr. Wool, 45, who lives in the Grant Houses in Morningside Heights.

For Michael Watson, an artist who lives in Harlem, winning the competition is a chance to build his art business, Fable Jones Studios.

During the pandemic, Mr. Watson started drawing and painting more and saved up enough money to open a gallery in Bushwick, Brooklyn, in 2020. There, Mr. Watson, 35, displayed his watercolors and also showcased works from other local artists, musicians and performers, most of whom were people of color.

But he had to close the gallery a year later after the landlord rented the space to someone else. Mr. Watson plans to reopen in another location. For now, though, he is considering all his options.

“I haven’t spent a dime of the money yet because I want to make sure the plan I have is the best plan,” he said. “I don’t want to make any mistakes.”