Lena Horne: Boogie Woogie Dream

From Wikipedia:

In a nightclub, Teddy Wilson and his orchestra are laying down their last groove for the night. In the audience, Mr. Weathercoop (Russel Morrison) and his date (Virginia Pine) briefly discuss Wilson's band. Back in the kitchen, where Albert Ammons is hanging paper and Pete Johnson tunes a piano, a kitchen maid (Lena Horne) begins to sing about how she would like to perform in a new gown, rather than to wash dishes. Pete Johnson provides an impromptu accompaniment, and then Ammons joins in on a duet; a cutaway informs us that the Weathercoops are paying attention.

The Weathercoops fall asleep, and this leads to a dream where the kitchen maid has gotten her evening gown; she introduces Ammons and Johnson, who play Boogie Woogie Dream. Teddy Wilson then conjures up his band and backs up the maid, with some help from Johnson, on the song Unlucky Woman. This is followed by a jam with Wilson's band, illustrated by a montage. Ammons, Johnson and the kitchen maid are then seen sleeping, propped up at the piano; the phone rings and wakes them up. Mr. Weathercoop ends up with the call, and afterward gives the others the offer that they have been dreaming about.