Banana leaves are key ingredients around the world in tropical cuisines. Consequently, while their culinary usage is far from exclusive to tropical Asian countries, they are quite common in the food of much of southeast Asia.
Culinarily, they’re mostly used as either a container in which to cook food or as a surface on which to eat. For cooking, a ubiquitous technique across many cuisines is to wrap food in a banana leaf and then steam or bake it, similar to how corn husks are used in other parts of the world. When used as a wrap for steaming or baking, the contents of the banana leaf vessel will end up with a subtle banana flavor imparted upon them. Via this method, you can cook almost anything — meats, fish, stuffed doughs, rice, plantains, vegetables, paneer and other cheeses, and mixtures of lots of things put together.
The other great thing about banana leaves is that they’re an inexpensive bulk item! At Uwajimaya, you can find them in the grocery department’s frozen section. If you plan on using the leaves within a week or less, you only need to keep them refrigerated. Otherwise, you can store them in the freezer where they’ll last for quite a long time.