Rolling Out the Dough

1. Beat butter and powdered sugar: Start by creaming together the soft butter and powdered sugar in a mixing bowl until smooth.
2. Incorporate egg yolk: Add the egg yolk to the butter-sugar mixture and mix until well combined.
3. Add plain flour: Gradually add the sifted plain flour to the mixture, stirring until a smooth dough forms.
4. Chill the dough: Transfer the dough onto baking paper, cover it with another sheet of baking paper, and roll it out into a sheet about 3-4 mm thick. Place it in the freezer for 15 minutes to firm up.