• In a large bowl, beat the butter for about 2 minutes until soft and creamy. Add in the sugar, vanilla extract and egg yolks. Beat together until you get a smooth and creamy consistency.
  ⅔ cups butter, ⅔ cups granulated sugar , 1 teaspoon vanilla extract , 2 egg yolks
• In a separate bowl, combine the flour, cornstarch and salt. Sieve the dry ingredients into the wet ingredients and knead to a firm cookie dough.
  2 cups all-purpose flour, ½ cups cornstarch / corn flour, 1 pinch salt
• Add your start tip to your piping bag. Place small amounts of dough into the bag and squeeze out around 5 cm/ 2 inch large circles. It is a tough dough, so do not worry if it takes longer.
• Place your ready-piped cookies onto a tray lined with baking parchment. You need to cool the dough for at least 30 minutes (or 60 min is even better) so it does not lose shape in the oven.
• In the meantime, preheat your oven to 200°C/392°F.After cooling, bake your cookies for about 15-20minutes. The exact baking time depends on your oven.

To decorate

• Melt the chocolate in a water bath or microwave.
• Dip half of each cookie into the melted chocolate and place on the baking parchment to dry.