Cheesy oat biscuits

Method

1. Heat the oven to 180°C/160°C fan/gas 4. Put the oatmeal, oatbran, flour and butter in a bowl and rub together with your fingertips to get a crumb-like texture. Add the salt, gruyère, cayenne and 175ml cold water, then knead for 2 minutes to work it into a dough. Shape into a disc, wrap in cling film and chill for 30 minutes.
2. Roll out on a lightly floured surface to a 24cm x 30cm rectangle (2mm thick). Use a sharp knife to cut 30 x 3cm x 8cm biscuits and put on a baking sheet lined with non-stick baking paper. Bake for 16 minutes until pale, golden and smelling biscuity. Cool on a wire rack. Serve or store in a sealed container.