Karlsbad Rings or Venecky z Varenych Zloutku
Cream the butter and powdered sugar until pale and fluffy. Add in sieved egg yolks, vanilla extract, lemon zest and a pinch of salt.
Beat until well combined. Add in flour and work to a smooth cookie dough.
Wrap the dough with cling film and chill for an hour. Preheat the oven to 180°C. Line two baking trays with parchment paper.
Remove the dough from the fridge and roll out between two sheets of parchment paper to 3mm thick.
Use a 5cm-diameter waved shaped cookie cutter to cut out the cookies and place them on the prepared trays.
Brush the rings with lightly beaten egg and sprinkle white sugar crystals or chopped almonds on top.
Bake for about 15 minutes or until just beginning to brown around the edges.
Cool cookies completely on a wire rack and store in an airtight container.