Barbacoa generally refers to meats or a whole sheep slow cooked over an open fire, or more traditionally, in a hole dug in the ground covered with maguey leaves, although the interpretation is loose, and in the present day and in some cases may refer to meat that was steamed until tender. Barbacoa de cabeza is a specialty of slow cooked cow head that arose in the ranching lands of northern Mexico after the Spanish conquest. Except for cochinita pibil, one of the common characteristics of Mexican barbacoa is that marinades are not used and sauces are not applied until the meat is fully cooked (for examples of Mexican marinades, see carne de chango and carne al pastor). Pork cooked in this manner is generally referred to as carnitas rather than barbacoa.Throughout Mexico, from pre-Colombian times to the present, barbacoa (the name derives from the Caribbean indigenous Taino barabicu) was the original Mexican barbecue, utilizing the many and varied moles (pronounced "mol-ehs", from Nahuatl molli) and salsa de molcajete, which were the first barbecue sauces. Game, turkey, and fish along with beans and other side dishes were slow cooked together in a pit for many hours. Following the introduction of cattle, pigs, goats, sheep, and chickens by the Spanish, the meat of these animals was cooked utilizing the traditional indigenous barbacoa style of cooking.In the U.S., barbacoa is often prepared with parts from the head of a cow, such as the cheeks. In northern Mexico, barbacoa is also sometimes made with the head of a cow, but more often it is prepared with goat meat or cabrito. In central Mexico the meat of choice is lamb, and in the Yucatan their traditional version, cochinita pibil (pit-style pork) is prepared with pork.Barbacoa was adopted into the cuisine of the southwestern United States by way of Texas which had formerly been a part of northern Mexico. The word transformed in time to "barbecue", together with many other words related to ranching and cowboy (vaquero) life. Considered a specialty meat, some meat markets only sell barbacoa on weekends or holidays in certain parts of south Texas and in all of Mexico.A traditional Mexican way of eating barbacoa is having it served on a warm soft taco style corn tortilla with guacamole and salsa for added flavor. In some parts of Texas it is eaten with onions, diced cilantro and a squirt of lime. Famous venues for barbacoaThe large food court of the tianguis (public market) of Chiconcuac in the state of Mexico, outside of Mexico City, seats hundreds of diners who are served barbacoa de borrego (mutton barbecue) and other regional specialties by dozens of open-air restaurants.Restaurante Arroyo, the world's largest Mexican restaurant, located in the Tlalpan district of Mexico City, is principally famous for its pit-roasted barbacoa de borrego and consomme de borrego, soup made from the drippings of the roasting lamb and sheep.Across the México-Pachuca highway there are many barbacoa stands at the road's side serving drivers. Pachuca is widely known as the homeland of barbacoa.