minstrel show

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A comic variety show of the 1800s and early 1900s, usually featuring white actors in blackface.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A variety show performed by white people in blackface.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a variety show in which the performers are made up in blackface
• noun a troupe of performers in blackface typically giving a comic program of negro songs and jokes