Daun Salam -
[Daun Salam (Indonesian), Salam Leaf, Indian Bay Leaf (obsolete),
Native to Borneo through Indonesia, this leaf is used in cooking only in that region - but in Indonesia in particular it is used a lot. Fresh leaves are used in curries and with meat, and dried leaves when fresh are not available. Packages of dried leaves are often labeled "Indian Bay Leaf", an obsolete usage from when Indonesia was called East India.
Many cookbooks, presuming you can't get Daun Salam, suggest using European bay leaves. This is bad advice - Salam is not at all related to either European or Indian bay leaves, both of which are highly aromatic Laurels with an entirely different and more powerful flavor. Daun Salam is a myrtle. The leaves are thinner and less aromatic, more earthy, and with a definite hint of citrus. A much better substitute is Curry Leaf (which is a citrus). Certainly not exact, but at least in the ballpark.
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Buying: Fresh leaves are not yet available in Los Angeles, and if not here, good luck finding them anywhere. Dried leaves are, however, available in Asian markets that have a significant Malay or Indonesian clientele, and they work decently.
Cooking: Some in Indonesia say the subtle flavor of Salam leaf is enhanced by frying a moment before mixing with other ingredients (as is often done in India with curry leaf), but Gernot Katzer found no significant flavor enhancement from this procedure. He did find that letting fresh leaves wither and dry for a few days did increase yield of essential oil..