Banana leaves have a wide range of applications because they are large, flexible, waterproof and decorative. They are used for cooking, wrapping and food-serving in a wide range of cuisines in tropical and subtropical areas. They are used for decorative and symbolic purposes in numerous Hindu and Buddhist ceremonies. In traditional homebuilding in tropical areas, roofs and fences made with dry banana-leaf thatch. Banana and palm leaves were historically the primary writing surfaces in many nations of South and Southeast Asia.
Like green tea, banana leaves contain large amounts of polyphenols, including EGCG. They also contain polyphenol oxidase, an enzyme that produces L-DOPA, a treatment for Parkinson’s disease.
In Indonesia, most people used banana leaf in cooking such as pepes and botok; They wrap the food using banana leaf then steamed, boiled, or grilled it on charcoal. Banana leaves are also used to wrap several kinds of snacks, such as nagasari or kue pisang and otak-otak, and also to wrap pressed sticky-rice such as lemper and lontong.
In Java, banana leaf is also used as a plate in shallow conical bowl called “pincuk”, usually to serve pecel or rujak cingur. The pincuk secured with lidi semat (small thorn-like pins made from the coconut-leaf midrib). The pincuk fit in the left palm, while the right hand is used to consume the food. It also functions as a traditional disposable take-away food container. The cleaned banana leaf is often used as a placemat; cut banana-leaf sheets placed on rattan, bamboo or clay plates are used to serve food. Decorated and folded banana leaves on woven bamboo plates are used as serving trays, tumpeng rice cones, and holders for jajan pasar.
More about banana leaves can be read here.