Mix together the flours and salt, add the water and mix to a dough. Knead on a clean work surface for about five minutes (don't use extra flour for kneading - it won't help and it will make your dough too dry). Shape into a ball and leave to rest in a covered, clean bowl for at least 30 minutes, preferably about an hour - this allows the gluten to swell with water and makes the dough more elastic.
Turn the dough out onto a lightly floured surface and divide into 12 pieces. Shape these into balls, then roll out with a rolling pin into circles about 2mm thick, lightly flouring the work surface and pin as you go to stop the dough sticking.
Melt the butter.
Heat a heavy based frying pan to medium hot, then cook the breads one at a time, turning every 30 seconds or so. When large bubbles start to appear, press then gently with a spatula - this will spread them and help the inside to puff up even more. The bread is ready when you can see no raw patches of dough. There should be some lightly scorched patches and plenty of big air pockets - sometimes they balloon up completely. Remove from the pan, brush with melted butter and either serve immediately or stack wrapped in a clean tea towel to keep them warm and soft.
«The dough can be prepared well ahead. Portion into balls, lightly oil each one and keep them in a tray in the fridge, covered with clingfilm, for up to two days.»