A native of New York, Hennebach was adopted as an infant and raised in Newark, New Jersey. Classically trained on piano, as a youngster, Hennebach won many statewide piano competitions in the Garden State. Hennebach sharpened her skills as a pianist at Oberlin Conservatory in Ohio, where she earned a bachelor's degree in music. Continuing her studies at Guildhall of Music and Drama in London, England, Hennebach shifted her focus to music therapy. Earning a master's degree, Hennebach returned to New York, where she has balanced her musical career by working as a music therapist with children diagnosed with cancer. Those experiences have inspired many of her songs.

In the late 1980s, Hennebach became involved with the Fast Folk Musical Magazine and the Songwriters' Cooperative. In addition to accompanying such artists as John Gorka, Suzanne Vega, Cliff Eberhardt, Shawn Colvin and Jack Hardy during Fast Folk revues at the Bottom Line in New York, Hennebach toured and/or recorded with Richard Shindell, Rod MacDonald and Paul Winter. Together with Adrienne Jones and Diane Chodkowski, Hennebach performed for three years with Madwoman in the Attic, a group that the Hartford Advocate named Best Acoustic Act in 1995 and 1996.

Hennebach has recently been performing in a duo that she shares with her husband, Mark Saunders, a graduate of the Hartford Conservatory in classical guitar; she issued Big Love in 1998.