In a large bowl, mix the flours, sea salt, sugar and bicarbonate of soda together. Pour in the liquid, bringing a soft dough together and, working quickly (the soda will start work immediately), shape into a shallow round loaf about 4cm thick or into a log then score into pieces of the desired size.

Sprinkle some flour over and bake in a pre-heated oven (220C/gas mark 8), the bread should be ready after 20-25 minutes. Turn it over and tap the bottom, it should sound hollow. Remove from the oven leaving to cool slightly before eating.