Preheat your oven to 190°C (375°F).
Line one large baking sheet with parchment paper and set aside.
Start by sifting the flour into a bowl, along with the chopped pecan pieces, salt and cornstarch. Mix these together until combined and place to one side.
In a separate, large mixing bowl, add the vegan butter and whisk until it looks more like a paste. Then add in the powdered sugar a little at a time and cream together until smooth.
Once you have a smooth, slightly lighter mixture, add in the vanilla extract and mix until combined.
Add the flour mixture to the butter and sugar and mix it with a spoon until a dough forms. If you find it's a little dry, add a small splash of milk or water.
Once you have your cookie dough, make individual balls by rolling the dough in your hands.
Place your balls on the prepared baking sheet - with plenty of space between each ball.
Bake for 8-10 minutes (or until the tops of your balls have started to go golden brown).
Leave the cookies to cool on the baking tray for 5 minutes, roll them in the powdered sugar and return the balls back to the cooling rack to cool completely.
Once completely cool, dust the tops of your balls with more powdered sugar - and you're done!