The breeding and cross-breeding of chickens has a long and quite possibly glorious history, extending over continents and centuries. The Rock Cornish hen or Rock Cornish game hen is a cross between the Cornish Game and Plymouth or White Rock breeds of chicken. The leading attribute of the breed is that it develops a relatively large breast in a short period of time. By the time the chickens are slaughtered at 4 to 6 weeks, they weigh around 2.5 pounds, and provide about one serving of meat each.
Jonathan Bartlett, author of The Cook’s Dictionary and Culinary Reference, says "it needs marinating or spicing to have much taste and is generally roasted." High praise, indeed.