Here's their official blurb...
Drawing upon a plethora of musical traditions from North Africa, the music Asefa presents is a blend of North African grooves and song traditions with passionate and innovative composition and improvisation. This is Mitteleuropean proto-blues. This is music that honors both ritual and experimentation, reminding us of the vitality and variety within the Jewish tradition -- a tradition that reflects the world. Listen and trace your own roots, whatever they are.They've got an album out. I haven't heard the whole thing yet, but the tracks on the website sound great. I'd link to them, but I'm a live show guy. I'd rather show off this clip from one of their concerts at New York's Blue Note Jazz Club
In addition to playing Asefa, Thomas conducts a variety of workshops
"Whether you want to discover more about Middle Eastern musical traditions, Sephardic poetry, or simply have an interactive experience touring different world musics, the educational programming and performance workshops add incredible value to any Asefa experience! "
To give you a sense of what he's about, here's a short talk by Thomas about his experience with Arab Jewish music given to the Brooklyn Historical Society - Roundtable: Arab Music Traditions and Their History in Brooklyn.