Joan Armatrading

Take Van Morrison, add a pinch of Joni Mitchell and Laura Nyro, shake it all up and serve it on the rug of a sweet, sensual, and powerful voice that sometimes evokes that of the much more celebrated Tracy Chapman, et voilà: Joan Armatrading!
Little known to the general public, she has written a couple of absolute masterpieces, but her entire body of work operates at decidedly high levels, blending soul, folk, reggae, gospel, blues, and rock in perfect harmony.