What Pambazo means
Pambazo is a Mexican antojito name of Spanish origin meaning "low bread". It comes from Italian pan basso (low bread), through Spanish. It is pronounced pam-BAH-soh, and it is most associated with Mexico City.
The word first named a cheap coarse wheat loaf of the colonial period. The guajillo-dipped sandwich took its name from the bread, not the other way round. The same word names both the bread roll and the guajillo-dipped torta made from it.
This is a site about what Mexican words mean, so there is no recipe here. For the name itself: Antojito means "little craving". These are the masa-based street foods named for their shape more often than their filling: a sope is a small mound, a huarache is a sandal, a gordita is a fat little one, a tlacoyo is an oval patty.
