• In a stand mixer with a paddle attachment or a large bowl add in the butter, sugar, vanilla extract, and lemon zest and beat on medium speed until light and fluffy. Scrape down the sides of the bowl of a stand mixer.
• Add in the egg yolk and mix until just combined and then add in the dry ingredients to the stand mixer and mix until the dough is formed. Divide the dough and flatten it into discs. Wrap each disc tightly in plastic wrap and allow it to chill for 2 hours until firm.
• Preheat your oven to 350 degrees.
• Line two separate baking sheets with parchment paper.
• Working with one dough disc at a time, place your dough on a lightly floured surface. With your rolling pin roll your dough to ¼ inch thickness. Cut your dough with your cookie cutter of choice place it on a prepared baking sheet and let it chill in the fridge for 15 minutes before baking.
• Roll out your second disc of dough and repeat the same steps as before but this time use a smaller cookie cutter, to cut out the center of the cookies. With the remaining dough can reroll your scraps of dough to get more cookies. Place your cookie cutouts on the cookie sheets and chill in the fridge for 15 minutes.
• Bake your first tray for 8 to 10 minutes. The cookies should have golden brown edges, allow them to cool for 5 minutes before transferring to a wire rack. Continue to bake the second tray of cookies until done. When the 2nd tray of cookies is done baking allow them to cool on the tray.

Linzer Cookie Assembly

• With the second tray dust the tops of the cut-out cookies generously with powdered sugar.
• Spread a little less than a teaspoon of jam on the bottom cookies and then place the dusted powdered sugar ones on top. Gently press the cookies together to form sandwich cookies.
• The cookies can be enjoyed immediately but will taste better the next day and for days to come.
• To store the cookies place them in a single layer in an airtight container at room temperature for up to 3 days.