Lime leaves come from the Kaffir Lime Tree, native to Indonesia. They are easily recognizable by their emerald-green,doubled sections, which makes them appear as if two leaves are joined together.
Lime leaves are commonly used in Laotian and Thai curry paste, adding an aromatic, astringent flavor. The leaves are used in Indonesian cuisine (especially Balinese and Javanese), for foods such as sayur asam, and are used along with Indonesian bay leaf for chicken and fish. They are also found in Malaysian and Burmese cuisines.
The leaves can be used fresh or dried, and can be stored frozen. The juice and rinds of kaffir limes are used in traditional Indonesian medicine; for this reason the fruit is referred to in Indonesia as jeruk obat (“medicine citrus”). The oil from the rind has strong insecticidal properties. The juice is generally regarded as too acidic to use in food preparation, but finds use as a cleanser for clothing and hair in Thailand.
Try adding some fresh leaves to a hot bath. You will need to try this to believe the delightful fragrance that will waft from your bathwater.
Bruise a few leaves and add to an outdoor citrus-scented potpourri, the scent will linger in the evening air when eating outdoors.