Add Butter (2 cup), Granulated Sugar (1 cup), Egg (1), All-Purpose Flour (1 cup), and Vanilla Extract (1 teaspoon) into a mixer and beat in low speed until well incorporated. Then put the dough on a floured work surface.
Knead the dough a little, then use a roll pin to roll out the dough until it's 4 to 5 millimeter thick. Use a cookie cutter to cut out the cookies. With a smaller one, cut a hole in the middle. Place the cookies in a baking tray lined with parchment paper. Bake at 170 degrees C (340 degrees F) for 15 minutes.
Once cool down, fill the cookies in fillings of choice. Then sprinkle some Powdered Confectioners Sugar (to taste). Serve and enjoy!