1.Place the dried yeast in a bowl. Add the lukewarm water (at least 37 °C) while stirring. Leave to rise for 15 minutes.
2.Mix the two flours together with the salt in a large bowl.
3.Pour the lukewarm water and the raised yeast into the flour mixture, and mix roughly using a spatula. When this becomes difficult, start kneading with your hands. The mixture does not have to be kneaded for too long, just enough for your dough to be consistent. If it is too sticky, add some white flour.
4.Leave the dough in the bowl and cover with a damp towel. Leave to stand for 2 hours.
5.Prepare a large clean bowl and brush the bottom with a little oil.
6.After 2 hours form a ball, folding over the sides. Place the side with the edges folded over in the bottom of the bowl. Cover again.
7.Place the Pyrex® casserole dish in the oven and preheat to 230 °C for 15 minutes.
8.Remove the casserole dish from the oven and place the dough ball inside, turning it over so that the folded sides are on top. Place the lid on the casserole dish and bake for 30 minutes.
9.After 30 minutes, remove the lid from the dish to make the crust crispy and continue cooking for 15 minutes.
10.Remove the bread from the oven and allow to cool before serving.