According to Wikipedia, Carne seca ('dried meat' in Spanish) is a type of dried beef used in Mexican cuisine.
According to Marian Burros of the New York Times, carne seca is a popular meat filling used by Tucson-area Mexican restaurants in enchiladas, chimichangas, and tacos, and is mixed with eggs.[
Did you know it makes a great jerky too?
Click here for the recipe: http://www.cdkitchen.com/recipes/recs/438/Carne_Seca49539.shtml