1. Heat the milk until it is just warm to the touch.
2. Pour the milk into a bowl and dissolve the yeast in it.
3. Add the sesame seeds, salt and 2 types of flour (reserve some of the flour for later).
4. Beat all the ingredients for the dough with a large spoon. Let the dough rise, covered, for approx. 30 min.
5. Pre-heat a baking sheet in the oven.
6. Tip the dough out onto a floured surface and knead thoroughly.
7. Divide the dough into 2 portions and roll each one into a rectangle (approx. 30 x 40 cm) – make sure there is plenty of flour on the worktop.
8. Cut the dough into 24 squares (approx. 10 x 10 cm).
9. Place the squares on sheets of baking parchment and prick with a fork.
10. Slide the baking parchment onto the hot baking sheet, and bake – one tray at a time – on the highest shelf.
11. Bake for about 5 min. at 225°C on one side, then turn the crispbread over and finish baking.