Line two large baking trays with parchment paper or silicone baking mats and set aside. Preheat oven to 160°C / 140°C Fan / Gas Mark 3. Cream the softened vegan baking block and the sugar until light and pale in colour (about 1-2 minutes).
Now sift the flours and add to the creamed baking block and sugar mixture along with the vanilla extract. Continue to mix until a crumbly and soft ball of dough comes together. Don’t overwork the dough, try to touch it as little as possible. At this point you can wrap the dough in clingfilm and chill it for 15 minutes, however this is an optional step - it does make rolling the dough out easier.
On a lightly floured surface roll the dough out to about 1/2 cm thickness. Using your favourite biscuit/cookie cutters, cut out shapes from the dough and transfer to the lined baking trays. Sprinkle the top of each biscuit with a little extra sugar or you can dust each baked biscuit with icing sugar after baking if you prefer.
Bake the biscuits for 15-20 minutes until they’re crisp and slightly golden around the edges - all ovens are different so they may need baking for longer. I like adding a little extra sugar to the tops at this point.
Once baked, leave to cool on the baking trays for 5-10 minutes, then carefully transport to a wire rack and allow the biscuits to cool completely to room temperature. Shortbread will keep in an airtight container for up to one week.