This rather bland definition leaves out the fact that corn husks are not required. In many parts of Mexico banana leaves are used. The "corn flour" described is actually made from corn that has been soaked in an alkaline solution, often lye that removes the outer husk. It is then known as masa, or masa harina if dried. Tamales can be filled with any number of fillings depending on what part of Mexico although pork and chicken are the most popular. There are also sweet tamales, served at holidays, that can be studded with dried fruits and nuts and spiced with cinnamon.