In a mixing bowl, stir together the flours, oatmeal, oats, ground ginger, salt and bicarbonate of soda.Rub in the butter.Stir in the sugar and chopped stem ginger.Add just enough of the beaten egg to bring together into a firm dough: don't add too much or the dough will be sticky. Sprinkle your work surface with wholemeal flour and lightly knead the dough into a smooth ball.Lightly flatten the dough, wrap in foil or cling film and chill in the fridge for at least 30 minutes.

While the dough is chilling: - preheat the oven to 180C/160C fan/Gas 4.- line two baking trays with baking paper.

Divide the dough in half, rewrap one half and put it back in the fridge.

Dust your worksurface and rolling pin with wholemeal flour, then roll out the first half of dough approximately 3-4 mm thick.Stamp out biscuits using a 6-7 cm cutter and put them on a baking tray: leave space between them as they will spread.Gather the scraps, re-roll and stamp out more biscuits, keeping the work surface and rolling pin well-floured.Repeat with the second half of dough.

Put the trays towards the middle of the oven and bake until golden brown and cooked all the way through (approx 15-18 min): don't worry if the biscuits are still a little soft at this point: they will firm up as they cool.

Leave the biscuits to cool on the trays for a few minutes then transfer to a wire rack until completely cold. They should be crisp when cold.Stored in an airtight container the biscuits should keep for at least a week.