Chipas are basically baked cheese buns and are very popular in Argentina.
These buns are made with cassava (tapioca) flour. This flour, also known also as manioc or tapioca starch, is very light can be found in health food stores or Hispanic markets.
Traditional chipas are made only with cheese, but different varieties can have ham or other cold meats in the filling. You can use Parmesan cheese by itself or a combination of hard and semi-hard cheeses, such as Manchego, Swiss or various Latin American cheeses.
Whatever you use, you'll end up with an exquisite little bun.