Curry leaves (curry leaf ) is used in Indian cooking. The leaves look a bit like bay leaves along a long central stem and are used in a similar fashion. The pungent leaves are typically toasted in oil prior to the rest of the ingredients being added to the cooking pan. The leaves are best fresh but can be found frozen as well as dried.
This suggestion is from a Chowhound post on uses for fresh curry leaves:
my favourite way to add curry leaves to dishes is at the end, and with mustard seed. Heat a small amount of oil in a pan, add 1 tsp black mustard seeds (cover this, they pop), after they pop, add a handful of curry leaves...you can then add this flavored oil to anything as a finisher....it's a very nutty, herbaceous way to add umami to a veg. dish