I've baked dozens of cookie recipes over the years, but this 1 recipe is most requested year over year

To make the vanilla drizzle, whisk together the powdered sugar, milk, and vanilla extract until smooth. Adjust the consistency by adding more milk if needed.
Drizzle the icing over the cooled cookies using a spoon or a small piping bag.
Allow the drizzle to set before serving or storing the cookies in an airtight container.

Variations & Tips
For a different twist, you can use other fruit preserves like strawberry or apricot in place of raspberry. If you prefer a citrus flavor, add a bit of lemon zest to the shortbread dough. To make the cookies more festive, consider sprinkling some finely chopped nuts or decorative sugar over the top before baking. If you're short on time, you can use store-bought shortbread for a quick version of this treat.