Mix all ingredients from corn flour to rapeseed oil. Pour 250 ml of hot water over it and make a dough out of it. Cover 3 baking sheets with parchment paper and distribute the dough evenly on them.
Using a foil (cut open the 3 liter freezer bag), roll out the dough very thinly or press it flat with your hands and foil. Sprinkle some sea salt on top. Bake all 3 baking trays at the same time at 150! C fan oven for about 1 hour until everything is lightly browned.
After cooling, break into pieces and store in a can.
The crispbread is more suitable for nibbling in between meals or while watching TV. It is a little too thin to cover.