At sixteen she ran away from home, got married, had a child and went back to school to study 'o' and 'A' levels and later attended London University (Queen Mary College) where she received a degree in English Literature.

In 1992, Souter moved to the U.S., working as a freelance writer for the international press, including the London Times, Guardian, Independent, The Daily Telegraph, Elle, Elle Decoration, House Beautiful, Vogue, Sydney Morning Herald, and South China Morning Post.

[7] She had her first professional gig at New York's Caffe San Marco in February 1999 and recorded her first album, Listen Love (Nara) in 2004.

In 2018, Souter released Picture in Black and White (NOA), which was the second of her albums to be chosen by the British Sunday Times magazine as a Jazz CD of the Year.

She has performed and/or recorded with Lynne Arriale, Alan Broadbent, Alec Dankworth, Billy Drummond, Joel Frahm, David Gilmore, Jim Hart, Nikki Iles, Howard Johnson, Steve Kuhn, Dana Leong, Joe Locke, Romero Lubambo, Marvin Sewell, Lew Soloff, and Kenny Werner, Jay Leonhart, Luis Perdomo, Yotam Silberstein, Clarence Penn, Yasushi Nakamura and Keita Ogawa.