Dutch Butter Nut Cookies

Preheat your oven to a moderate temperature of 300 degrees Fahrenheit (or equivalently, 150 degrees Celsius). Prepare two baking sheets by lining them with parchment paper.

Combine the butter and sugar in a mixing bowl using an electric mixer until they reach a light and airy consistency. Introduce the egg yolk into the mixture, blending it until everything is fully incorporated and smooth.

Add flour and cinnamon to the mixture, stirring until the dough comes together as a cohesive unit.

Distribute two-thirds of the dough onto one baking sheet, covering it evenly. Place the remaining dough on half of the second baking sheet, spreading it out to cover most of its surface. Use your fingers to press down on the dough and create a textured pattern, then use a fork to scratch a design into its surface.

In a separate bowl, whisk together the egg white and water until they form a smooth, liquid mixture. Brush this mixture lightly over the dough to add moisture and shine.

Add a layer of walnuts on top of the dough, sprinkling them evenly to create a crunchy texture.

Place the baking sheets in the preheated oven and bake for 30 minutes, allowing the cookies to cook through.

Remove the baking sheets from the oven and immediately cut the cookies into 24 equal-sized squares or rectangles. Allow them to cool completely on the baking sheets before separating and serving.