Beat the flour, butter, agave syrup, egg yolks, the seeds from the vanilla pod and a pinch of salt together in a stand mixer to make a smooth dough. Wrap the dough and chill for 30 minutes.
Roll out the dough on a lightly floured worksurface and cut out 36 cookies with biscuit cutters.
Heat the oven to 180C/fan 160C/gas 4. Cover 2 baking sheets with baking parchment. Lift the cookies onto the baking sheets and bake for 8-10 minutes until golden. Allow to cool completely. Store in an airtight container.