Core and roughly cut tomatoes. Roughly chop the onions as well and let both stand overnight with a handful of salt and a little sugar.
Squeeze the tomatoes and onions, simmer with the dates, figs, sugar, vinegar and mustard for about 1.5 hours. Then add the spices and simmer for another 10 minutes. Mix the flour with water and bind the relish with it.
Pour hot into sterilized twist-off jars (230 ml) and close.