Pianist Bolcom has had a highly-respected separate career as a Pulitzer Prize-winning composer of symphonies, classical music, and three operas commissioned by the Chicago Lyric Opera, for which he has also received the National Medal of Arts. Morris is a mezzo-soprano whose done some separate performing and directing. But it is their popular concerts and 24 albums together for which they're best known. And still recording and giving concerts.
Here's one, for example. The wonderful and hugely popular "Meet Me in St. Louis." But with the verses that are what the song is actually about.