Made from brined and fermented krill, this salty pink or brown paste is a signature ingredient of Indonesian cooking. The smell is intense and unappealing to many – even some Indonesian cooks choose to leave it out –but once cooked it recedes quietly to become a back note of umami and richness rather than fishiness. Use very sparingly in a similar way to Thai fish sauce. Sold either wet or dry, it needs to be toasted before use. If it is not being fried in a bumbu, I toast terasi in a dry frying pan until it releases its pungent odour leaving the paste brown and crumbly. It keeps almost forever in an airtight container, which will also keep the smell confined.