Kluwek

Pangium edule. The seeds of a large tree, dark red or black inside, an important ingredient of rawon and some other dishes. Dried kluwek can be bought in Holland; these must be soaked for 30 minutes before being ground up. Fresh kluwek can contain hydrocyanic acid, which must be made harmless either by repeated boiling and washing, or by heating for 10–15 minutes in the embers of a fire.