Double hit today for the Guatemalan Slang category.
Shuco(a) is the Guatemalan slang for dirty. Shuco is also used for Guatemalan hot dog. The Guatemalan shuco hot dog comes with guacamol (avocado sauce), boiled cabbage, mayonnaise, tomato sauce, mustard, hot sauce, and one or more of the following: chorizo (Guatemalan red sausage), longaniza (Guatemalan white sausage), salchicha (normal hot dog sausage), ham, bacon, pepperoni, german ham and sausages, chichen breast, beef steak fajitas, polish sausages, et-cetera.
Chapin(a) is the self-imposed gentilic noun and adjective equivalent to Guatemalan. Although the official gentile in Spanish for Guatemalan is guatemalteco, very often Guatemalans use the word chapin instead.
So a shuco chapin would be a Guatemalan hot dog. The brand shuckoshapin is playing with the phonetic spelling of the words.