I have been growing this black chili for many years now. Many chili plants tend to die after they bear fruit for a few months so it is essential to keep some seeds. Pollinate the flowers yourself if you don't want your chili to hybridise with other types nearby.
This is the leaf used in one of Singapore's most famous dish "Laksa". There are many variations to this S.E.Asian dish, each having its own unique blend of spices and consequently leading to very different taste. For example, Penang Laksa does not use this leaf at all.
The very popular hawker snack "otak-otak" also uses this leaf.
This herb is very easy to grow. First go to the market and get a handful of the herb, pluck off most of the leaves leaving only the top un-plucked. Stick the 5-6 inch stems into the ground and water them every morning. You will soon have so much of the herb you'll want to give some away.