Leslie was born in Brooklyn and raised in the woods of New York’s Hudson Valley, where she grew up in a musical and creatively rich household. Initially drawn to the visual arts, she ultimately found her path in music, focusing on the bassoon. She earned an MFA from the California Institute of the Arts and a BA from Middlebury College, later teaching at Pepperdine University, Santa Monica College, and ArtCenter College of Design.

Leslie has performed with numerous prestigious ensembles including the Los Angeles and Israel Philharmonics, the Los Angeles Opera, Bolshoi Ballet, and the Hollywood Bowl Orchestra. Her extensive film soundtrack credits include Jurassic Park, The Lion King, The Matrix trilogy, and Star Trek X. She has toured globally with conductors such as Zubin Mehta, Leonard Bernstein, and Esa-Pekka Salonen, and her own compositions have been featured at festivals around the world.

A multi-disciplinary artist, Leslie often blends music with dance improvisation, performance art, and multimedia collaborations. She lives in Los Angeles with her husband, guitarist and composer Stan Ayeroff, and their son Zander, an actor and video editor. Her latest passion is gardening.