At the moment, McDonald's is featuring her songs in two adverts.

They are the latest in a string of high-profile gigs for Heller, an active member of West Los Angeles' Pico-Robertson Jewish community.

In addition to the non-kosher fast food chain, Walmart has licensed Heller's music for one of its summer commercials, and her songs have appeared in ads for American Airlines, Hasbro, Lifetime, MTV, Nickelodeon, the Disney Channel and Disneyland.

Some may scoff at the idea as "selling out", but in a business that's been in decline since the dawn of the internet, it's a concept that's irrelevant today.

"Because the margins are so small on selling a record on iTunes, and people aren't paying for an album to get the single they want, you don't make money selling albums or touring any more unless you already have a following," she said.

"The reason you know of artists such as Ingrid Michaelson, Imagine Dragons and Snow Patrol is because they license their music."

Licensing her heartfelt music to film, television and commercials forms the core of Heller's strategy to define success in the music world on her own terms.

Operating with a do-it-yourself model, Heller writes and publishes her music under her own business, Catch the Moon Music - and, perhaps most important, she nets all the proceeds when she secures a licensing deal.

"I'm the only artist, as far as I know, who has pitched my own work and gotten this far," she said.

It may be lucrative, but her work is also a conscious effort to bring something positive into the world.

"This is why I write songs called Let Your Colors Shine, which is all about how each of us has a spark and it's so important to share it," she said.

"I write songs like This Is It, which is all about knowing each moment is all we really have and living it to the fullest. I write songs called Spread a Little Love, all about coming together and spreading the love along.

"All my songs aspire to [express] a message of hope and remind people how special they are and that they're not alone."

A native Floridian, the 36-year-old moved to Los Angeles 12 years ago as an aspiring singer-songwriter after spending two years in Israel studying Torah.

That experience, which cemented her spiritual connection to Jewish tradition, never left her.

Heller's Jewish identity and her spiritual practice, which includes observing Shabbat, provide the chorus to her work week.

"It keeps me grounded and I always know where my North Star is," she said.

"I don't get caught up in the superficial part of the business, which allows me to really just enjoy making music. It reminds me of who I am and what I'm really here to do.

"It helps give me clarity and purpose, and it impacts every song I write and every interaction I have."

The married mother sends her two girls, aged two and three, to a Conservative synagogue pre-school to help infuse them with their own sense of spirituality.

"I feel very connected to Hashem and I want so much for my kids to have that connection to God, to know the source of all life and wisdom, and to know the source of their soul," she said.

"I want them to know they carry an infinite spark and they have amazing potential and great responsibility to be a light."

Being a 'light' unto others is something she takes seriously.

"I love being able to use the contacts I've built to help other artists launch their careers," says Heller, who conducts workshops to assist other singer-songwriters in navigating the shifting music industry.

She also represents other artists seeking to license their work.

Heller says she began singing as far back as she can remember, with the dream of one day landing her compositions in films and television.

She studied piano and voice as a child and performed musical theatre before graduating from Florida State University.

Early in her career, Heller received critical advice to maintain a "polite persistence," and that's something she estimates accounts for 90 per cent of her working strategy.

"You can't take rejection personally and must just keep going," she revealed.

"So much happens for the people who keep showing up - and it doesn't hurt when your motives are really to spread a little goodness."

Heller's first licensing deal was with Kodak in 2007. Another big break came in 2009, when NBC licensed her single Turn the Sunshine On for a promotional campaign for its comedies, including the American version of The Office.

"That was pretty fantastic and gave me lots of exposure," she said.

Over the years, Heller's music has been part of the soundtrack for poignant and sweet moments on TV programmes, including Pretty Little Liars and One Tree Hill.

"Usually, fans find my music because they'll hear a song in a show or in an ad and then they'll come to find the rest of the songs on iTunes," said Heller.

"I want to inspire more and more people and touch more souls to know they have a deep, intrinsic goodness.

"Songwriting and performing give me so much fulfilment. I feel so expressed and I get to lift other people, so it's such a win-win."

cathyheller.com