I had been trying to find banana leaves, cldnt find them at any of the Indian stores. I finally found some at the frozen section at ShopRite. When thawed these are as good as the fresh banana leaves.
Heat a dosa tawa & place the banana leaf on it. Flip when one side starts to change color. Let it stay on the tawa for just 2-3mins. This is done so that the leaf does not tear when it is being folded.
Pour one spoonful of batter on the banana leaf & spread it with the back of the spoon. Place 1-2 spoonful of the jaggery mixture in the middle.