Pour in the milk and mix just until the dough comes together.
Chill & Bake
Divide the dough into two disks, wrap each in plastic wrap, and chill for at least 1 hour or up to 24 hours.
Preheat the oven to 350°F (175°C). Line baking sheets with parchment paper.
On a lightly floured surface, roll one disk of dough to 1/8-inch thickness. Cut out shapes and place 1 inch apart on prepared sheets.
Bake 8–10 minutes, until edges are just turning golden. Let cookies rest on the sheet for 5 minutes, then transfer to a wire rack to cool completely.
Notes
Always wash hands and utensils after handling raw egg to prevent cross-contamination.Chilling the dough ensures crisp edges and better shape retention; you can freeze cut shapes for up to 3 months.Store cooled cookies in an airtight container at room temperature for up to 3 days or refrigerate for up to a week.