The seeds in these crackers are worth tracking down if you want to make a really special batch of savoury biscuits. Cut these crackers into diamond shapes by making straight line cuts right across the rolled pastry. These biscuits will keep well for two weeks in an airtight container.
Nigella seeds are the black seeds you sometimes see on Turkish bread and Ajowan seeds are a small pale-brown seeds that look like celery and have a thyme-like flavour.