Vanilla shortbread

Method

1. Using a knife, scrape along the cut side of the vanilla pod to remove the seeds. Place the seeds in a large bowl with the sugar and mix well (store the vanilla pod in a jar of sugar to flavour the sugar). Add the butter and mix with a wooden spoon until lightly creamed. Add the flour and a pinch of salt, then mix to a soft dough. Turn out, wrap in cling film and chill for 1 hour or overnight.
2. On a lightly floured surface, roll the dough out until about 5mm thick. Use an 8cm round fluted cutter to cut out the biscuits, re-rolling the trimmings to make 24. Transfer to 2 large, greased baking trays. Sprinkle with sugar, then chill for 10 minutes.
3. Meanwhile, preheat the oven to 160C/fan140C/gas 3. Bake the biscuits for about 15 minutes, swapping the trays around halfway, until pale golden. Transfer to a wire rack to cool and crisp up. Place the shortbread in a large storage jar ready to take to the picnic.