Add the flour, cubed butter and salt to a food processor. Blitz until the mixture resembles coarse crumbs.
Always processing, pour in the cold wine. The dough will start to form and gather into a ball within seconds from the addition of the liquid. Stop the processor as soon as it shapes up.
Divide the dough into 2 balls using a kitchen scale to make them equal. Tightly wrap both balls in plastic wrap. One will go into the fridge to chill 20 minutes before using, while the other can be stored in the freezer for the next time you will need to make a shortcrust tart. If short on time, you can skip the chilling but be aware that the dough might be quite soft to work.
Press the dough into a tart pan and prick the bottom and sides with a fork. Pre-bake in the preheated oven at 200°C (390°F) for 10 minutes before adding the filling and continuing to bake your savoury pie.