Iced Shortbread Cookies
Beat the butter, sugar, salt, vanilla sugar and egg yolk until smooth and creamy. Stir in the cognac, nutmeg and flour and mix until well combined. Place the dough between two layers of plastic wrap, roll out to 4 mm (approximately 1/8 inch) thick and refrigerate for 2 hours.
Preheat the oven to 180°C (approximately 350°F). Cut the dough into shapes (such as stars, animals, etc.) using the cookie cutter of your choice. Place on a baking sheet lined with parchment paper and bake for 12 minutes, until golden brown.
Remove, the cookies from the oven and cool on a wire rack.
Whisk together the powdered sugar and lemon juice until smooth. Divide the icing into 2 or 3 portions and mix with assorted food colorings. Spread the icing onto the cooled cookies and allow to dry.