Preheat the oven to Gas Mark 4/180°C/fan oven 160°C. Line two baking trays with non stick baking parchment.

Place the margarine in a warmed mixing bowl and sift in the icing sugar Cream them together until you have a pale and fluffy mixture.

Using a small, sharp knife, slice the vanilla pod in half lengthways. Scoop out the tiny black seeds and beat them into the creamed mixture. Add the flour and cornflour and mix to form a stiff dough.

Divide the dough into 16 small balls. Arrange them well apart on the baking sheets and press them down with a fork.

Bake for 12 - 15 minutes until just golden. Cool on the baking trays for 10 minutes, and then, using a spatula, transfer them to a wire rack to allow them to cool and become crisp.

If you prefer, use ground mixed spice or cinnamon to flavour the melting moments instead of vanilla.