Heat the oven to 180°C/160°C fan/350°F/gas mark 4. Cut two pieces of baking parchment the same size as a large baking tray, approximately 30 x 40cm (12 x 16in).

Thoroughly mix the dried ingredients together in a mixing bowl with a spoon and then stir in the water to form a into smooth, thick dough.

Put this into the centre of a piece of the baking parchment on the work surface and put the other on top. Use your hands to push the mixture down and then use a rolling pin to roll the dough our evenly to a thickness of 3mm. Use a knife to move some of the dough around and also to neaten the edges to form a rectangle that almost fills the tray. Slowly peel away the top sheet of parchment and make sure there aren’t any holes. If there are, gently push the mixture together with your finger dipped in water (to stop it sticking to you).

Use a cook’s knife or wiggly pasta cutter to score lines in the dough to form crackers around 5cm x 5cm. Now transfer this base sheet onto a baking tray and put into the oven for 15–17 minutes or until golden brown.

Remove the crackers from the oven and slide the paper once more onto the work surface. Now break up break up the crackers along the scored lines. Leave them to cool for a few minutes then transfer to a cooling rack.

The crackers will keep in an airtight container for up to 3 days or a week in the fridge. If they do soften, re-bake them in a hot oven for a few minutes. You can also freeze them.