Pamonha is a paste made from corn and milk, wrapped in a corn husk and boiled. It is consumed in different parts of Brazil, but it's usually sweet in the Southeast and salty in the Central-West.
The ingredients for pamonha are basically the same as for curau, but while curau is stirred in a pan till it thickens, pamonhas are wrapped in a corn husk and boiled.
In some Brazilian cities, pamonhas are sold in cars with loudspeakers that blare catchy lines. Those may vary according to local flights of fancy, but the original text was created to advertise pamonhas made in Piracicaba, SP by the Rodrigues family and distributed to several other areas in Brazil.
For tourists, one of the best times to eat fresh pamonhas is during Festas Juninas, or June Festivals. Throughout the year, you'll find the treat at specialized shops such as roadside chain Rancho da Pamonha or places like Casa da Pamonha, in Manaus, or Frutos da Terra, in Goiânia.
Correction: Thanks to reader Jonasblau, who alerted me in the Brazil Forum to the original Pamonhas de Piracicaba text. The information in this article has been corrected and the reference to a local version of the original has been removed.