Hungarian Walnut Crescent Cookies (Hókifli)

Ingredients

For the Dough

• 2 ½ cups all-purpose flour
• 1 cup unsalted butter, softened
• ¼ cup powdered sugar
• 2 egg yolks
• 1 teaspoon vanilla extract
• 2–3 tablespoons sour cream
• Pinch of salt

For the Walnut Filling

• 1 ½ cups finely ground walnuts
• ½ cup granulated sugar
• ¼ cup milk
• 1 teaspoon vanilla extract
• 1 teaspoon lemon zest
• ½ teaspoon cinnamon

For Finishing

• 1 cup powdered sugar