Preheat the oven to 150 C / Gas 2. Line a baking tray with baking parchment.
Combine the butter and sugar in a bowl and mix well until light and fluffy. Add the vanilla, mix, then add the flour and mix well. Transfer to a lightly floured surface, and using a rolling pin, roll out to a thickness of about 5mm. Cut into shapes of your choice then transfer to the prepared baking tray.
Bake for 25 minutes or until golden brown. Remove from the oven and allow to cool on a cooling rack before decorating, if desired, and serving.