Jenni studied composition and piano at the Guildhall School of Music where she then taught following her graduation. She was part of a team of teachers working with creative performance skills for classical musicians on the Performance and Communication Skills programme. She ran community composition projects and facilitated improvisation classes for both undergraduates and postgraduates.

Jenni has composed and presented two full length operas, 'The Descent of Inanna' (1992, 1994, 1997, 1998 and 2009) and 'Siddhartha Spirit Child' (2001) both commissioned and produced by the ensemble Lontano. Inanna was presented this year in a 'bare bones' version at the Arcola Theatre's Grimeborn festival, under the musical direction of Alex Ingram.  A distinctive feature of both Jenni's operas is the use of singing styles across genres and improvisation within the score.

Recently she has concentrated on smaller scale work; songs and extended pieces at the piano and at the guitar, as well as for small chamber ensembles.