In a large mixing bowl sift together flour and corn starch.
Stir in hazelnuts, vanilla sugar, and powdered sugar. If you don't have vanilla sugar or can't find it, leave it out.
Using a pastry blender or your fingertips, work in the vegetable shortening; work it in until it all disappears and it's well blended.
Cover dough with plastic wrap and put in the fridge for 15 to 30 minutes.
Preheat oven to 350.
Line two baking sheets with silpat mat or parchment paper; set aside.
Remove dough from fridge and let rest for 5 minutes.
Flour your work surface and rolling pin; roll out the dough to a 1/4-inch thickness.
Cut out cookies with a round cutter and transfer to prepared pan. You don't have to space them a lot - the cookies will not spread.
Bake for 13 minutes.
Let cool on pan for 5 minutes; remove and cool on wire racks.
When completely cooled, dip them in Nutella and top with edible glitter or raw sugar.