Put the flours, salt, yeast, butter, treacle and water into a bowl and mix for five minutes. Tip out onto a lightly floured surface and knead for five minutes, then put the dough back in the bowl and leave for one hour to rise.
Line a baking tray. Incorporate the figs and dates into the dough, then divide it into two pieces. Shape the pieces into balls, place on the baking tray and leave to rise for one hour.
Preheat the oven to 220ºC/425ºF/mark 7. Dust the loaves with flour and, using a knife, make three equidistant horizontal cuts all around each ball. Bake for thirty minutes, then transfer to a wire rack to cool.