Place the flours, caraway seeds, salt and yeast in a large bowl or in the bowl of a standing mixer.
Stir the oil and honey into the water and pour into the flour mix.
Mix it into rough dough using the mixer’s dough hook attachment or a large wooden spoon. Leave the dough to rest for 20 minutes.
Now knead the dough with the mixer dough hook at medium speed or by hand on a floured surface until it’s smooth and elastic, clears the sides of the bowl or stops sticking to your hands.
Leave it to prove in a warm place for 1-1 ½ hour until doubled in size.
Preheat the oven to 230C/450F/gas 8. Line a 30 x 20cm (or larger) baking tray with parchment and sprinkle it lightly with flour.
Turn the dough out onto a floured surface. Pat it gently into a 20cm or so square. Fold the top half to the centre, then fold its corners on top, like ears. Turn the dough round 180 degrees and do the same with the other side. Now fold in half stretching the outer surface and seal the seam.
Place the loaf, seam side down, in the prepared tray. Cover with oiled cling film and prove for 30-40 minutes.
When it’s appreciably risen, slash 3 times across the top and transfer into the oven. Immediately turn the heat down to 190C/375F/gas 5. Bake for 35 to 40 minutes.
In the meantime make the glaze: in a small pan dissolve the cornflour in the water. Bring it to the boil and simmer until it thickens and becomes clear.
Remove the bread from the oven onto a wire rack (with the parchment, so that you don’t make a mess) and brush, hot, with the glaze all over the top and sides.
Sprinkle with salt crystals and extra caraway. Let it cool completely before slicing.
