Asian chefs often prefer to retain the succulence of chicken breasts by poaching or steaming them in wrappers that also enclose flavour-imparting ingredients, such as lemon grass stalks.
Cut a banana leaf into four squares, each one large enough to envelop a chicken breast. Brush each centre with a 1:1 hoisin and soy sauce mix. Place a chicken breast on each and top with lemon grass and a few slices of fresh root ginger. Spoon over more soy sauce.
Warp each leaf square around the chicken breast to make a neat parcel and secure with string if necessary. Place 1-2 packages at a time in a steamer basket over simmering water and cook for 15 minutes. Serve the chicken breasts in their banana leaves to be unwrapped at the table.