In a large mixing bowl, add flour, unsalted butter, and sugar. Use an electric mixer to blend until creamy. Add marzipan, vanilla extract, egg yolks, and salt. Mix thoroughly, but be careful not to overmix.

Shape the dough into a disc and wrap it tightly in cling film. Refrigerate for at least 30 minutes.

Preheat your oven to 350°F (175°C). Dust a surface with flour and roll out the chilled dough to about ¼ inch thick. Use cookie cutters to cut out shapes and place them on a baking sheet lined with parchment paper.

Brush the tops of the cookies with a beaten egg wash if desired for a shiny finish.

Bake for 12-15 minutes until the edges are lightly golden. Remove and let cool on the baking sheet before transferring to a wire rack.